diff --git a/advanced/driveActivity.gs b/advanced/driveActivity.gs
index 3d5f8bd0f..b139dfe72 100644
--- a/advanced/driveActivity.gs
+++ b/advanced/driveActivity.gs
@@ -19,21 +19,21 @@
  * unique users that performed the activity.
  */
 function getUsersActivity() {
-  var fileId = 'YOUR_FILE_ID_HERE';
+  const fileId = 'YOUR_FILE_ID_HERE';
 
-  var pageToken;
-  var users = {};
+  let pageToken;
+  const users = {};
   do {
-    var result = AppsActivity.Activities.list({
+    let result = AppsActivity.Activities.list({
       'drive.fileId': fileId,
       'source': 'drive.google.com',
       'pageToken': pageToken
     });
-    var activities = result.activities;
-    for (var i = 0; i < activities.length; i++) {
-      var events = activities[i].singleEvents;
-      for (var j = 0; j < events.length; j++) {
-        var event = events[j];
+    const activities = result.activities;
+    for (let i = 0; i < activities.length; i++) {
+      const events = activities[i].singleEvents;
+      for (let j = 0; j < events.length; j++) {
+        const event = events[j];
         users[event.user.name] = true;
       }
     }
diff --git a/advanced/iot.gs b/advanced/iot.gs
index 8087fd023..4f9739183 100644
--- a/advanced/iot.gs
+++ b/advanced/iot.gs
@@ -18,12 +18,12 @@
  * Lists the registries for the configured project and region.
  */
 function listRegistries() {
-  console.log(response);
-  var projectId = 'your-project-id';
-  var cloudRegion = 'us-central1';
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion;
+  const projectId = 'your-project-id';
+  const cloudRegion = 'us-central1';
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion;
 
-  var response = CloudIoT.Projects.Locations.Registries.list(parent);
+  const response = CloudIoT.Projects.Locations.Registries.list(parent);
+  console.log(response);
   if (response.deviceRegistries) {
     response.deviceRegistries.forEach(
         function(registry) {
@@ -38,23 +38,23 @@ function listRegistries() {
  * Creates a registry.
  */
 function createRegistry() {
-  var cloudRegion = 'us-central1';
-  var name = 'your-registry-name';
-  var projectId = 'your-project-id';
-  var topic = 'your-pubsub-topic';
+  const cloudRegion = 'us-central1';
+  const name = 'your-registry-name';
+  const projectId = 'your-project-id';
+  const topic = 'your-pubsub-topic';
 
-  var pubsubTopic = 'projects/' + projectId + '/topics/' + topic;
+  const pubsubTopic = 'projects/' + projectId + '/topics/' + topic;
 
-  var registry = {
+  const registry = {
     'eventNotificationConfigs': [{
       // From - https://console.cloud.google.com/cloudpubsub
       pubsubTopicName: pubsubTopic
     }],
     'id': name
   };
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion;
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion;
 
-  var response = CloudIoT.Projects.Locations.Registries.create(registry, parent);
+  const response = CloudIoT.Projects.Locations.Registries.create(registry, parent);
   console.log('Created registry: ' + response.id);
 }
 // [END apps_script_iot_create_registry]
@@ -64,14 +64,14 @@ function createRegistry() {
  * Describes a registry.
  */
 function getRegistry() {
-  var cloudRegion = 'us-central1';
-  var name = 'your-registry-name';
-  var projectId = 'your-project-id';
+  const cloudRegion = 'us-central1';
+  const name = 'your-registry-name';
+  const projectId = 'your-project-id';
 
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion;
-  var registryName = parent + '/registries/' + name;
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion;
+  const registryName = parent + '/registries/' + name;
 
-  var response = CloudIoT.Projects.Locations.Registries.get(registryName);
+  const response = CloudIoT.Projects.Locations.Registries.get(registryName);
   console.log('Retrieved registry: ' + response.id);
 }
 // [END apps_script_iot_get_registry]
@@ -81,14 +81,14 @@ function getRegistry() {
  * Deletes a registry.
  */
 function deleteRegistry() {
-  var cloudRegion = 'us-central1';
-  var name = 'your-registry-name';
-  var projectId = 'your-project-id';
+  const cloudRegion = 'us-central1';
+  const name = 'your-registry-name';
+  const projectId = 'your-project-id';
 
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion;
-  var registryName = parent + '/registries/' + name;
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion;
+  const registryName = parent + '/registries/' + name;
 
-  var response = CloudIoT.Projects.Locations.Registries.remove(registryName);
+  const response = CloudIoT.Projects.Locations.Registries.remove(registryName);
   // Successfully removed registry if exception was not thrown.
   console.log('Deleted registry: ' + name);
 }
@@ -99,14 +99,14 @@ function deleteRegistry() {
  * Lists the devices in the given registry.
  */
 function listDevicesForRegistry() {
-  var cloudRegion = 'us-central1';
-  var name = 'your-registry-name';
-  var projectId = 'your-project-id';
+  const cloudRegion = 'us-central1';
+  const name = 'your-registry-name';
+  const projectId = 'your-project-id';
 
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion;
-  var registryName = parent + '/registries/' + name;
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion;
+  const registryName = parent + '/registries/' + name;
 
-  var response = CloudIoT.Projects.Locations.Registries.Devices.list(registryName);
+  const response = CloudIoT.Projects.Locations.Registries.Devices.list(registryName);
 
   console.log('Registry contains the following devices: ');
   if (response.devices) {
@@ -123,15 +123,15 @@ function listDevicesForRegistry() {
  * Creates a device without credentials.
  */
 function createDevice() {
-  var cloudRegion = 'us-central1';
-  var name = 'your-device-name';
-  var projectId = 'your-project-id';
-  var registry = 'your-registry-name';
+  const cloudRegion = 'us-central1';
+  const name = 'your-device-name';
+  const projectId = 'your-project-id';
+  const registry = 'your-registry-name';
 
   console.log('Creating device: ' + name + ' in Registry: ' + registry);
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion + '/registries/' + registry;
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion + '/registries/' + registry;
 
-  var device = {
+  const device = {
     id: name,
     gatewayConfig: {
       gatewayType: 'NON_GATEWAY',
@@ -139,7 +139,7 @@ function createDevice() {
     }
   };
 
-  var response = CloudIoT.Projects.Locations.Registries.Devices.create(device, parent);
+  const response = CloudIoT.Projects.Locations.Registries.Devices.create(device, parent);
   console.log('Created device:' + response.name);
 }
 // [END apps_script_iot_create_unauth_device]
@@ -153,21 +153,21 @@ function createRsaDevice() {
   //    openssl req -x509 -newkey rsa:2048 -days 3650 -keyout rsa_private.pem \
   //      -nodes -out rsa_cert.pem -subj "/CN=unused"
   //
-  // **NOTE** Be sure to insert the newline charaters in the string varant.
-  var cert =
+  // **NOTE** Be sure to insert the newline charaters in the string constant.
+  const cert =
       '-----BEGIN CERTIFICATE-----\n' +
       'your-PUBLIC-certificate-b64-bytes\n' +
       '...\n' +
       'more-PUBLIC-certificate-b64-bytes==\n' +
       '-----END CERTIFICATE-----\n';
 
-  var cloudRegion = 'us-central1';
-  var name = 'your-device-name';
-  var projectId = 'your-project-id';
-  var registry = 'your-registry-name';
+  const cloudRegion = 'us-central1';
+  const name = 'your-device-name';
+  const projectId = 'your-project-id';
+  const registry = 'your-registry-name';
 
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion + '/registries/' + registry;
-  var device = {
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion + '/registries/' + registry;
+  const device = {
     id: name,
     gatewayConfig: {
       gatewayType: 'NON_GATEWAY',
@@ -181,7 +181,7 @@ function createRsaDevice() {
     }]
   };
 
-  var response = CloudIoT.Projects.Locations.Registries.Devices.create(device, parent);
+  const response = CloudIoT.Projects.Locations.Registries.Devices.create(device, parent);
   console.log('Created device:' + response.name);
 }
 // [END apps_script_iot_create_rsa_device]
@@ -191,15 +191,15 @@ function createRsaDevice() {
  * Deletes a device from the given registry.
  */
 function deleteDevice() {
-  var cloudRegion = 'us-central1';
-  var name = 'your-device-name';
-  var projectId = 'your-project-id';
-  var registry = 'your-registry-name';
+  const cloudRegion = 'us-central1';
+  const name = 'your-device-name';
+  const projectId = 'your-project-id';
+  const registry = 'your-registry-name';
 
-  var parent = 'projects/' + projectId + '/locations/' + cloudRegion + '/registries/' + registry;
-  var deviceName = parent + '/devices/' + name;
+  const parent = 'projects/' + projectId + '/locations/' + cloudRegion + '/registries/' + registry;
+  const deviceName = parent + '/devices/' + name;
 
-  var response = CloudIoT.Projects.Locations.Registries.Devices.remove(deviceName);
+  const response = CloudIoT.Projects.Locations.Registries.Devices.remove(deviceName);
   // If no exception thrown, device was successfully removed
   console.log('Successfully deleted device: ' + deviceName);
 }
diff --git a/data-studio/auth.gs b/data-studio/auth.gs
index 5035107ee..c595c188a 100644
--- a/data-studio/auth.gs
+++ b/data-studio/auth.gs
@@ -20,7 +20,7 @@
  * @return {object} The Auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.OAUTH2)
       .build();
@@ -33,7 +33,7 @@ function getAuthType() {
  * @return {object} The Auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.PATH_USER_PASS)
       .setHelpUrl('https://www.example.org/connector-auth-help')
@@ -47,7 +47,7 @@ function getAuthType() {
  * @return {object} The Auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.USER_PASS)
       .setHelpUrl('https://www.example.org/connector-auth-help')
@@ -61,7 +61,7 @@ function getAuthType() {
  * @return {object} The Auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.USER_TOKEN)
       .setHelpUrl('https://www.example.org/connector-auth-help')
@@ -75,7 +75,7 @@ function getAuthType() {
  * @return {object} The Auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.KEY)
       .setHelpUrl('https://www.example.org/connector-auth-help')
@@ -89,7 +89,7 @@ function getAuthType() {
  * @return {object} The Auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.NONE)
       .build();
@@ -110,7 +110,7 @@ function resetAuth() {
  * Resets the auth service.
  */
 function resetAuth() {
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.deleteProperty('dscc.path');
   userProperties.deleteProperty('dscc.username');
   userProperties.deleteProperty('dscc.password');
@@ -122,7 +122,7 @@ function resetAuth() {
  * Resets the auth service.
  */
 function resetAuth() {
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.deleteProperty('dscc.username');
   userProperties.deleteProperty('dscc.password');
 }
@@ -133,7 +133,7 @@ function resetAuth() {
  * Resets the auth service.
  */
 function resetAuth() {
-  var userTokenProperties = PropertiesService.getUserProperties();
+  const userTokenProperties = PropertiesService.getUserProperties();
   userTokenProperties.deleteProperty('dscc.username');
   userTokenProperties.deleteProperty('dscc.password');
 }
@@ -144,7 +144,7 @@ function resetAuth() {
  * Resets the auth service.
  */
 function resetAuth() {
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.deleteProperty('dscc.key');
 }
 // [END apps_script_data_studio_auth_reset_key]
@@ -165,10 +165,10 @@ function isAuthValid() {
  * @return {boolean} True if the auth service has access.
  */
 function isAuthValid() {
-  var userProperties = PropertiesService.getUserProperties();
-  var path = userProperties.getProperty('dscc.path');
-  var userName = userProperties.getProperty('dscc.username');
-  var password = userProperties.getProperty('dscc.password');
+  const userProperties = PropertiesService.getUserProperties();
+  const path = userProperties.getProperty('dscc.path');
+  const userName = userProperties.getProperty('dscc.username');
+  const password = userProperties.getProperty('dscc.password');
   // This assumes you have a validateCredentials function that
   // can validate if the userName and password are correct.
   return validateCredentials(path, userName, password);
@@ -181,9 +181,9 @@ function isAuthValid() {
  * @return {boolean} True if the auth service has access.
  */
 function isAuthValid() {
-  var userProperties = PropertiesService.getUserProperties();
-  var userName = userProperties.getProperty('dscc.username');
-  var password = userProperties.getProperty('dscc.password');
+  const userProperties = PropertiesService.getUserProperties();
+  const userName = userProperties.getProperty('dscc.username');
+  const password = userProperties.getProperty('dscc.password');
   // This assumes you have a validateCredentials function that
   // can validate if the userName and password are correct.
   return validateCredentials(userName, password);
@@ -196,9 +196,9 @@ function isAuthValid() {
  * @return {boolean} True if the auth service has access.
  */
 function isAuthValid() {
-  var userProperties = PropertiesService.getUserProperties();
-  var userName = userProperties.getProperty('dscc.username');
-  var token = userProperties.getProperty('dscc.token');
+  const userProperties = PropertiesService.getUserProperties();
+  const userName = userProperties.getProperty('dscc.username');
+  const token = userProperties.getProperty('dscc.token');
   // This assumes you have a validateCredentials function that
   // can validate if the userName and token are correct.
   return validateCredentials(userName, token);
@@ -211,8 +211,8 @@ function isAuthValid() {
  * @return {boolean} True if the auth service has access.
  */
 function isAuthValid() {
-  var userProperties = PropertiesService.getUserProperties();
-  var key = userProperties.getProperty('dscc.key');
+  const userProperties = PropertiesService.getUserProperties();
+  const key = userProperties.getProperty('dscc.key');
   // This assumes you have a validateKey function that can validate
   // if the key is valid.
   return validateKey(key);
@@ -243,7 +243,7 @@ function getOAuthService() {
  * @return {HtmlOutput} The HTML output to show to the user.
  */
 function authCallback(request) {
-  var authorized = getOAuthService().handleCallback(request);
+  const authorized = getOAuthService().handleCallback(request);
   if (authorized) {
     return HtmlService.createHtmlOutput('Success! You can close this tab.');
   } else {
@@ -270,22 +270,22 @@ function get3PAuthorizationUrls() {
  * @return {object} An object with an errorCode.
  */
 function setCredentials(request) {
-  var creds = request.userPass;
-  var path = creds.path;
-  var username = creds.username;
-  var password = creds.password;
+  const creds = request.userPass;
+  const path = creds.path;
+  const username = creds.username;
+  const password = creds.password;
 
   // Optional
   // Check if the provided path, username and password are valid through
   // a call to your service. You would have to have a `checkForValidCreds`
   // function defined for this to work.
-  var validCreds = checkForValidCreds(path, username, password);
+  const validCreds = checkForValidCreds(path, username, password);
   if (!validCreds) {
     return {
       errorCode: 'INVALID_CREDENTIALS'
     };
   }
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.setProperty('dscc.path', path);
   userProperties.setProperty('dscc.username', username);
   userProperties.setProperty('dscc.password', password);
@@ -302,21 +302,21 @@ function setCredentials(request) {
  * @return {object} An object with an errorCode.
  */
 function setCredentials(request) {
-  var creds = request.userPass;
-  var username = creds.username;
-  var password = creds.password;
+  const creds = request.userPass;
+  const username = creds.username;
+  const password = creds.password;
 
   // Optional
   // Check if the provided username and password are valid through a
   // call to your service. You would have to have a `checkForValidCreds`
   // function defined for this to work.
-  var validCreds = checkForValidCreds(username, password);
+  const validCreds = checkForValidCreds(username, password);
   if (!validCreds) {
     return {
       errorCode: 'INVALID_CREDENTIALS'
     };
   }
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.setProperty('dscc.username', username);
   userProperties.setProperty('dscc.password', password);
   return {
@@ -332,21 +332,21 @@ function setCredentials(request) {
  * @return {object} An object with an errorCode.
  */
 function setCredentials(request) {
-  var creds = request.userToken;
-  var username = creds.username;
-  var token = creds.token;
+  const creds = request.userToken;
+  const username = creds.username;
+  const token = creds.token;
 
   // Optional
   // Check if the provided username and token are valid through a
   // call to your service. You would have to have a `checkForValidCreds`
   // function defined for this to work.
-  var validCreds = checkForValidCreds(username, token);
+  const validCreds = checkForValidCreds(username, token);
   if (!validCreds) {
     return {
       errorCode: 'INVALID_CREDENTIALS'
     };
   }
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.setProperty('dscc.username', username);
   userProperties.setProperty('dscc.token', token);
   return {
@@ -362,19 +362,19 @@ function setCredentials(request) {
  * @return {object} An object with an errorCode.
  */
 function setCredentials(request) {
-  var key = request.key;
+  const key = request.key;
 
   // Optional
   // Check if the provided key is valid through a call to your service.
   // You would have to have a `checkForValidKey` function defined for
   // this to work.
-  var validKey = checkForValidKey(key);
+  const validKey = checkForValidKey(key);
   if (!validKey) {
     return {
       errorCode: 'INVALID_CREDENTIALS'
     };
   }
-  var userProperties = PropertiesService.getUserProperties();
+  const userProperties = PropertiesService.getUserProperties();
   userProperties.setProperty('dscc.key', key);
   return {
     errorCode: 'NONE'
diff --git a/data-studio/build.gs b/data-studio/build.gs
index ec845dba6..82a6d1299 100644
--- a/data-studio/build.gs
+++ b/data-studio/build.gs
@@ -21,8 +21,8 @@
  * @see https://developers.google.com/apps-script/reference/data-studio/config
  */
 function getConfig() {
-  var cc = DataStudioApp.createCommunityConnector();
-  var config = cc.getConfig();
+  const cc = DataStudioApp.createCommunityConnector();
+  const config = cc.getConfig();
 
   config.newInfo()
       .setId('instructions')
@@ -48,10 +48,10 @@ function getConfig() {
  * @see https://developers.google.com/apps-script/reference/data-studio/fields
  */
 function getFields() {
-  var cc = DataStudioApp.createCommunityConnector();
-  var fields = cc.getFields();
-  var types = cc.FieldType;
-  var aggregations = cc.AggregationType;
+  const cc = DataStudioApp.createCommunityConnector();
+  const fields = cc.getFields();
+  const types = cc.FieldType;
+  const aggregations = cc.AggregationType;
 
   fields.newDimension()
       .setId('packageName')
@@ -78,7 +78,7 @@ function getFields() {
  * @return {object} The schema.
  */
 function getSchema(request) {
-  var fields = getFields().build();
+  const fields = getFields().build();
   return {'schema': fields};
 }
 // [END apps_script_data_studio_build_get_fields]
@@ -94,7 +94,7 @@ function getSchema(request) {
 function responseToRows(requestedFields, response, packageName) {
   // Transform parsed data and filter for requested fields
   return response.map(function(dailyDownload) {
-    var row = [];
+    let row = [];
     requestedFields.asArray().forEach(function(field) {
       switch (field.getId()) {
         case 'day':
@@ -117,13 +117,13 @@ function responseToRows(requestedFields, response, packageName) {
  * @return {object} The data.
  */
 function getData(request) {
-  var requestedFieldIds = request.fields.map(function(field) {
+  const requestedFieldIds = request.fields.map(function(field) {
     return field.name;
   });
-  var requestedFields = getFields().forIds(requestedFieldIds);
+  const requestedFields = getFields().forIds(requestedFieldIds);
 
   // Fetch and parse data from API
-  var url = [
+  const url = [
     'https://api.npmjs.org/downloads/range/',
     request.dateRange.startDate,
     ':',
@@ -131,9 +131,9 @@ function getData(request) {
     '/',
     request.configParams.package
   ];
-  var response = UrlFetchApp.fetch(url.join(''));
-  var parsedResponse = JSON.parse(response).downloads;
-  var rows = responseToRows(requestedFields, parsedResponse, request.configParams.package);
+  const response = UrlFetchApp.fetch(url.join(''));
+  const parsedResponse = JSON.parse(response).downloads;
+  const rows = responseToRows(requestedFields, parsedResponse, request.configParams.package);
 
   return {
     schema: requestedFields.build(),
@@ -148,7 +148,7 @@ function getData(request) {
  * @return {object} The auth type.
  */
 function getAuthType() {
-  var cc = DataStudioApp.createCommunityConnector();
+  const cc = DataStudioApp.createCommunityConnector();
   return cc.newAuthTypeResponse()
       .setAuthType(cc.AuthType.NONE)
       .build();
diff --git a/data-studio/errors.gs b/data-studio/errors.gs
index e6cdc1719..f48fd1a7c 100644
--- a/data-studio/errors.gs
+++ b/data-studio/errors.gs
@@ -57,7 +57,7 @@ function throwConnectorError(message, userSafe) {
  *    the log entry.
  */
 function logConnectorError(originalError, message) {
-  var logEntry = [
+  const logEntry = [
     'Original error (Message): ',
     originalError,
     '(', message, ')'
diff --git a/data-studio/semantics.gs b/data-studio/semantics.gs
index 426eb47e1..8b6af6837 100644
--- a/data-studio/semantics.gs
+++ b/data-studio/semantics.gs
@@ -15,7 +15,7 @@
  */
 
 // [START apps_script_data_studio_manual]
-var schema = [
+const schema = [
   {
     'name': 'Income',
     'label': 'Income (in USD)',
diff --git a/forms-api/demos/AppsScriptFormsAPIWebApp/FormsAPI.gs b/forms-api/demos/AppsScriptFormsAPIWebApp/FormsAPI.gs
index 5be743b4e..6e36d003c 100644
--- a/forms-api/demos/AppsScriptFormsAPIWebApp/FormsAPI.gs
+++ b/forms-api/demos/AppsScriptFormsAPIWebApp/FormsAPI.gs
@@ -42,7 +42,7 @@ function create(title) {
   };
 
   console.log('Forms API POST options was: ' + JSON.stringify(options));
-  let response = UrlFetchApp.fetch(formsAPIUrl, options);
+  const response = UrlFetchApp.fetch(formsAPIUrl, options);
   console.log('Response from Forms API was: ' + JSON.stringify(response));
 
   return ('' + response);
@@ -64,7 +64,7 @@ function get(formId) {
   };
 
   try {
-    let response = UrlFetchApp.fetch(formsAPIUrl + formId, options);
+    const response = UrlFetchApp.fetch(formsAPIUrl + formId, options);
     console.log('Response from Forms API was: ' + response);
     return ('' + response);
   } catch (e) {
@@ -103,7 +103,7 @@ function batchUpdate(formId) {
     'muteHttpExceptions': true,
   };
 
-  let response = UrlFetchApp.fetch(formsAPIUrl + formId + ':batchUpdate',
+  const response = UrlFetchApp.fetch(formsAPIUrl + formId + ':batchUpdate',
     options);
   console.log('Response code from API: ' + response.getResponseCode());
   return (response.getResponseCode());
@@ -116,7 +116,7 @@ function batchUpdate(formId) {
 function responsesGet(formId, responseId) {
   const accessToken = ScriptApp.getOAuthToken();
 
-  var options = {
+  const options = {
     'headers': {
       Authorization: 'Bearer ' + accessToken,
       Accept: 'application/json'
@@ -125,7 +125,7 @@ function responsesGet(formId, responseId) {
   };
 
   try {
-    var response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'responses/' +
+    const response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'responses/' +
       responseId, options);
     console.log('Response from Forms.responses.get was: ' + response);
     return ('' + response);
@@ -142,7 +142,7 @@ function responsesGet(formId, responseId) {
 function responsesList(formId) {
   const accessToken = ScriptApp.getOAuthToken();
 
-  var options = {
+  const options = {
     'headers': {
       Authorization: 'Bearer ' + accessToken,
       Accept: 'application/json'
@@ -151,7 +151,7 @@ function responsesList(formId) {
   };
 
   try {
-    var response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'responses',
+    const response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'responses',
       options);
     console.log('Response from Forms.responses was: ' + response);
     return ('' + response);
@@ -166,9 +166,9 @@ function responsesList(formId) {
  * POST https://forms.googleapis.com/v1/forms/{formId}/watches
  */
 function createWatch(formId) {
-  let accessToken = ScriptApp.getOAuthToken();
+  const accessToken = ScriptApp.getOAuthToken();
 
-  var myWatch = {
+  const myWatch = {
     'watch': {
       'target': {
         'topic': {
@@ -180,7 +180,7 @@ function createWatch(formId) {
   };
   console.log('myWatch is: ' + JSON.stringify(myWatch));
 
-  var options = {
+  const options = {
     'headers': {
       Authorization: 'Bearer ' + accessToken
     },
@@ -192,7 +192,7 @@ function createWatch(formId) {
   console.log('options are: ' + JSON.stringify(options));
   console.log('formsAPIURL was: ' + formsAPIUrl);
 
-  var response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches',
+  const response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches',
     options);
   console.log(response);
   return ('' + response);
@@ -203,11 +203,11 @@ function createWatch(formId) {
  * DELETE https://forms.googleapis.com/v1/forms/{formId}/watches/{watchId}
  */
 function deleteWatch(formId, watchId) {
-  let accessToken = ScriptApp.getOAuthToken();
+  const accessToken = ScriptApp.getOAuthToken();
 
   console.log('formsAPIUrl is: ' + formsAPIUrl);
 
-  var options = {
+  const options = {
     'headers': {
       Authorization: 'Bearer ' + accessToken,
       Accept: 'application/json'
@@ -217,7 +217,7 @@ function deleteWatch(formId, watchId) {
   };
 
   try {
-    var response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches/' +
+    const response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches/' +
       watchId, options);
     console.log(response);
     return ('' + response);
@@ -234,8 +234,8 @@ function deleteWatch(formId, watchId) {
  */
 function watchesList(formId) {
   console.log('formId is: ' + formId);
-  let accessToken = ScriptApp.getOAuthToken();
-  var options = {
+  const accessToken = ScriptApp.getOAuthToken();
+  const options = {
     'headers': {
       Authorization: 'Bearer ' + accessToken,
       Accept: 'application/json'
@@ -243,7 +243,7 @@ function watchesList(formId) {
     'method': 'get'
   };
   try {
-    var response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches',
+    const response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches',
       options);
     console.log(response);
     return ('' + response);
@@ -258,9 +258,9 @@ function watchesList(formId) {
  * POST https://forms.googleapis.com/v1/forms/{formId}/watches/{watchId}:renew
  */
 function renewWatch(formId, watchId) {
-  let accessToken = ScriptApp.getOAuthToken();
+  const accessToken = ScriptApp.getOAuthToken();
 
-  var options = {
+  const options = {
     'headers': {
       Authorization: 'Bearer ' + accessToken,
       Accept: 'application/json'
@@ -269,7 +269,7 @@ function renewWatch(formId, watchId) {
   };
 
   try {
-    var response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches/' +
+    const response = UrlFetchApp.fetch(formsAPIUrl + formId + '/' + 'watches/' +
       watchId + ':renew', options);
     console.log(response);
     return ('' + response);
diff --git a/forms-api/demos/AppsScriptFormsAPIWebApp/Main.html b/forms-api/demos/AppsScriptFormsAPIWebApp/Main.html
index 8612e1b37..b14d484bb 100644
--- a/forms-api/demos/AppsScriptFormsAPIWebApp/Main.html
+++ b/forms-api/demos/AppsScriptFormsAPIWebApp/Main.html
@@ -97,9 +97,9 @@
     }
 
     function create() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Creating new form...";
-      var newFormTitle = document.getElementById('newFormTitle');
+      const newFormTitle = document.getElementById('newFormTitle');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -119,9 +119,9 @@
     }
 
     function get() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Get form by id...";
-      var formId = document.getElementById('globalFormId');
+      const formId = document.getElementById('globalFormId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -135,9 +135,9 @@
     }
 
     function batchUpdate() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Batch update...";
-      var formId = document.getElementById('globalFormId');
+      const formId = document.getElementById('globalFormId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -153,9 +153,9 @@
 
 
     function responsesList() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Get form by id...";
-      var formId = document.getElementById('globalFormId');
+      const formId = document.getElementById('globalFormId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -169,10 +169,10 @@
     }
 
     function responsesGet() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Get response by id...";
-      var formId = document.getElementById('globalFormId');
-      var respId = document.getElementById('responseId');
+      const formId = document.getElementById('globalFormId');
+      const respId = document.getElementById('responseId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -186,9 +186,9 @@
     }
 
     function watchesList() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Get watches ...";
-      var formId = document.getElementById('globalFormId');
+      const formId = document.getElementById('globalFormId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -202,9 +202,9 @@
     }
 
     function createWatch() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Create watch ...";
-      var formId = document.getElementById('globalFormId');
+      const formId = document.getElementById('globalFormId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -218,10 +218,10 @@
     }
 
     function deleteWatch() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Delete watch ...";
-      var formId = document.getElementById('globalFormId');
-      var watchId = document.getElementById('watchId');
+      const formId = document.getElementById('globalFormId');
+      const watchId = document.getElementById('watchId');
 
       google.script.run
         .withFailureHandler(function(error) {
@@ -235,10 +235,10 @@
     }
 
     function renewWatch() {
-      var status = document.getElementById('status');
+      const status = document.getElementById('status');
       status.innerHTML = "Renew watch ...";
-      var formId = document.getElementById('globalFormId');
-      var watchId = document.getElementById('renewWatchId');
+      const formId = document.getElementById('globalFormId');
+      const watchId = document.getElementById('renewWatchId');
 
       google.script.run
         .withFailureHandler(function(error) {
diff --git a/forms-api/snippets/retrieve_all_responses.gs b/forms-api/snippets/retrieve_all_responses.gs
index 78a55ceeb..c7d865e6d 100644
--- a/forms-api/snippets/retrieve_all_responses.gs
+++ b/forms-api/snippets/retrieve_all_responses.gs
@@ -15,21 +15,21 @@
  # [START forms_retrieve_all_responses]
  function callFormsAPI() {
   console.log('Calling the Forms API!');
-  var formId = '<YOUR_FORM_ID>';
+  const formId = '<YOUR_FORM_ID>';
 
   // Get OAuth Token
- var OAuthToken = ScriptApp.getOAuthToken();
+ const OAuthToken = ScriptApp.getOAuthToken();
  console.log('OAuth token is: ' + OAuthToken);
- var formsAPIUrl = 'https://forms.googleapis.com/v1/forms/' + formId + '/' + 'responses';
+ const formsAPIUrl = 'https://forms.googleapis.com/v1/forms/' + formId + '/' + 'responses';
  console.log('formsAPIUrl is: ' + formsAPIUrl);
- var options = {
+ const options = {
     'headers': {
       Authorization: 'Bearer ' + OAuthToken,
       Accept: 'application/json'
     },
     'method': 'get'
   };  
-var response = UrlFetchApp.fetch(formsAPIUrl, options);
+const response = UrlFetchApp.fetch(formsAPIUrl, options);
  console.log('Response from forms.responses was: ' + response);
 }
 # [END forms_retrieve_all_responses]
diff --git a/slides/SpeakerNotesScript/scriptGen.gs b/slides/SpeakerNotesScript/scriptGen.gs
index 7e4841d57..d89938f84 100644
--- a/slides/SpeakerNotesScript/scriptGen.gs
+++ b/slides/SpeakerNotesScript/scriptGen.gs
@@ -42,25 +42,25 @@ function onOpen(e) {
  * with the speaker notes for each slide.
  */
 function generateSlidesScript() {
-  var presentation = SlidesApp.getActivePresentation();
-  var docTitle = presentation.getName() + ' Script';
-  var slides = presentation.getSlides();
+  const presentation = SlidesApp.getActivePresentation();
+  const docTitle = presentation.getName() + ' Script';
+  const slides = presentation.getSlides();
 
   // Creates a document in the user's home Drive directory.
-  var speakerNotesDoc = DocumentApp.create(docTitle);
+  const speakerNotesDoc = DocumentApp.create(docTitle);
   console.log('Created document with id %s', speakerNotesDoc.getId());
 
-  var docBody = speakerNotesDoc.getBody();
-  var header = docBody.appendParagraph(docTitle);
+  const docBody = speakerNotesDoc.getBody();
+  const header = docBody.appendParagraph(docTitle);
   header.setHeading(DocumentApp.ParagraphHeading.HEADING1);
 
   // Iterate through each slide and extract the speaker notes
   // into the document body.
-  for (var i = 0; i < slides.length; i++) {
-    var section = docBody.appendParagraph('Slide ' + (i + 1))
+  for (let i = 0; i < slides.length; i++) {
+    const section = docBody.appendParagraph('Slide ' + (i + 1))
         .setHeading(DocumentApp.ParagraphHeading.HEADING2);
 
-    var notes = slides[i].getNotesPage().getSpeakerNotesShape().getText().asString();
+    const notes = slides[i].getNotesPage().getSpeakerNotesShape().getText().asString();
     docBody.appendParagraph(notes)
         .appendHorizontalRule();
   }
diff --git a/slides/imageSlides/imageSlides.gs b/slides/imageSlides/imageSlides.gs
index 32dbd1b18..3214fa630 100644
--- a/slides/imageSlides/imageSlides.gs
+++ b/slides/imageSlides/imageSlides.gs
@@ -15,8 +15,8 @@
  */
 
 // [START apps_script_slides_image_create]
-var NAME = 'My favorite images';
-var deck = SlidesApp.create(NAME);
+const NAME = 'My favorite images';
+const deck = SlidesApp.create(NAME);
 // [END apps_script_slides_image_create]
 
 // [START apps_script_slides_image_add_image]
@@ -26,8 +26,8 @@ var deck = SlidesApp.create(NAME);
  * @param {number} index The slide index to add the image to
  */
  function addImageSlide(imageUrl, index) {
-  var slide = deck.appendSlide(SlidesApp.PredefinedLayout.BLANK);
-  var image = slide.insertImage(imageUrl);
+  const slide = deck.appendSlide(SlidesApp.PredefinedLayout.BLANK);
+  const image = slide.insertImage(imageUrl);
  }
 // [END apps_script_slides_image_add_image]
 
@@ -36,14 +36,14 @@ var deck = SlidesApp.create(NAME);
  * Adds images to a slides presentation.
  */
 function main() {
-  var images = [
+  const images = [
     'https://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png',
     'http://www.google.com/services/images/phone-animation-results_2x.png',
     'http://www.google.com/services/images/section-work-card-img_2x.jpg',
     'http://gsuite.google.com/img/icons/product-lockup.png',
     'http://gsuite.google.com/img/home-hero_2x.jpg'
   ];
-  var [title, subtitle] = deck.getSlides()[0].getPageElements();
+  const [title, subtitle] = deck.getSlides()[0].getPageElements();
   title.asShape().getText().setText(NAME);
   subtitle.asShape().getText().setText('Google Apps Script\nSlides Service demo');
   images.forEach(addImageSlide);
@@ -58,22 +58,22 @@ function main() {
  * @param {number} index The index into the array; unused (req'd by forEach)
  */
 function addImageSlide(imageUrl, index) {
-    var slide = deck.appendSlide(SlidesApp.PredefinedLayout.BLANK);
-    var image = slide.insertImage(imageUrl);
-    var imgWidth = image.getWidth();
-    var imgHeight = image.getHeight();
-    var pageWidth = deck.getPageWidth();
-    var pageHeight = deck.getPageHeight();
-    var newX = pageWidth/2. - imgWidth/2.;
-    var newY = pageHeight/2. - imgHeight/2.;
+    const slide = deck.appendSlide(SlidesApp.PredefinedLayout.BLANK);
+    const image = slide.insertImage(imageUrl);
+    const imgWidth = image.getWidth();
+    const imgHeight = image.getHeight();
+    const pageWidth = deck.getPageWidth();
+    const pageHeight = deck.getPageHeight();
+    const newX = pageWidth/2. - imgWidth/2.;
+    const newY = pageHeight/2. - imgHeight/2.;
     image.setLeft(newX).setTop(newY);
 }
 // [END apps_script_slides_image_add_image_slide]
 
 
 // [START apps_script_slides_image_full_script]
-var NAME = 'My favorite images';
-var presentation = SlidesApp.create(NAME);
+const NAME = 'My favorite images';
+const presentation = SlidesApp.create(NAME);
 
 /**
  * Creates a single slide using the image from the given link;
@@ -82,14 +82,14 @@ var presentation = SlidesApp.create(NAME);
  * @param {number} index The index into the array; unused (req'd by forEach)
  */
 function addImageSlide(imageUrl, index) {
-    var slide = presentation.appendSlide(SlidesApp.PredefinedLayout.BLANK);
-    var image = slide.insertImage(imageUrl);
-    var imgWidth = image.getWidth();
-    var imgHeight = image.getHeight();
-    var pageWidth = presentation.getPageWidth();
-    var pageHeight = presentation.getPageHeight();
-    var newX = pageWidth/2. - imgWidth/2.;
-    var newY = pageHeight/2. - imgHeight/2.;
+    const slide = presentation.appendSlide(SlidesApp.PredefinedLayout.BLANK);
+    const image = slide.insertImage(imageUrl);
+    const imgWidth = image.getWidth();
+    const imgHeight = image.getHeight();
+    const pageWidth = presentation.getPageWidth();
+    const pageHeight = presentation.getPageHeight();
+    const newX = pageWidth/2. - imgWidth/2.;
+    const newY = pageHeight/2. - imgHeight/2.;
     image.setLeft(newX).setTop(newY);
 }
 
@@ -98,14 +98,14 @@ function addImageSlide(imageUrl, index) {
  * main title & subtitle, and creation of individual slides for each image.
  */
 function main() {
-  var images = [
+  const images = [
     'http://www.google.com/images/branding/googlelogo/2x/googlelogo_color_272x92dp.png',
     'http://www.google.com/services/images/phone-animation-results_2x.png',
     'http://www.google.com/services/images/section-work-card-img_2x.jpg',
     'http://gsuite.google.com/img/icons/product-lockup.png',
     'http://gsuite.google.com/img/home-hero_2x.jpg'
   ];
-  var [title, subtitle] = presentation.getSlides()[0].getPageElements();
+  const [title, subtitle] = presentation.getSlides()[0].getPageElements();
   title.asShape().getText().setText(NAME);
   subtitle.asShape().getText().setText('Google Apps Script\nSlides Service demo');
   images.forEach(addImageSlide);