Added missing comma in "What is AWS"

Added missing comma in list of potential use cases in second paragraph.

Author: landermkerbey

doc_source/welcome.md

@@ -2,7 +2,7 @@
 
  AWS Lambda is a compute service that lets you run code without provisioning or managing servers\. AWS Lambda executes your code only when needed and scales automatically, from a few requests per day to thousands per second\. You pay only for the compute time you consume \- there is no charge when your code is not running\. With AWS Lambda, you can run code for virtually any type of application or backend service \- all with zero administration\. AWS Lambda runs your code on a high\-availability compute infrastructure and performs all of the administration of the compute resources, including server and operating system maintenance, capacity provisioning and automatic scaling, code monitoring and logging\. All you need to do is supply your code in one of the languages that AWS Lambda supports \(currently Node\.js, Java, C\#, Go and Python\)\. 
 
-You can use AWS Lambda to run your code in response to events, such as changes to data in an Amazon S3 bucket or an Amazon DynamoDB table; to run your code in response to HTTP requests using Amazon API Gateway; or invoke your code using API calls made using AWS SDKs\. With these capabilities, you can use Lambda to easily build data processing triggers for AWS services like Amazon S3 and Amazon DynamoDB process streaming data stored in Kinesis, or create your own back end that operates at AWS scale, performance, and security\.
+You can use AWS Lambda to run your code in response to events, such as changes to data in an Amazon S3 bucket or an Amazon DynamoDB table; to run your code in response to HTTP requests using Amazon API Gateway; or invoke your code using API calls made using AWS SDKs\. With these capabilities, you can use Lambda to easily build data processing triggers for AWS services like Amazon S3 and Amazon DynamoDB, process streaming data stored in Kinesis, or create your own back end that operates at AWS scale, performance, and security\.
 
 You can also build [serverless](https://aws.amazon.com/serverless) applications composed of functions that are triggered by events and automatically deploy them using AWS CodePipeline and AWS CodeBuild\. For more information, see [Deploying Lambda\-based Applications](deploying-lambda-apps.md)\.
 
@@ -36,4 +36,4 @@ The following topics provide additional information about AWS Lambda:
 + [AWS Lambda Function Versioning and Aliases](versioning-aliases.md)
 + [Using Amazon CloudWatch](monitoring-functions.md)
 + [Best Practices for Working with AWS Lambda Functions](best-practices.md)
-+ [AWS Lambda Limits](limits.md)
++ [AWS Lambda Limits](limits.md)