Fix some typos

Also changed some words for clarity

lessons2.json

@@ -81,7 +81,7 @@
             "href" : "software-win.php"
         },
         {
-            "title" : "Setting up the PythonLearn Environment in Macintosh",
+            "title" : "Setting up the PythonLearn Environment on a Macintosh",
             "href" : "software-mac.php"
         },
         {
@@ -284,7 +284,7 @@
     "title": "Strings",
     "anchor": "strings",
     "icon" : "fa-file-text-o",
-    "description": "We look at how Python stores and mnipulates textual data using string variables and functions.",
+    "description": "We look at how Python stores and manipulates textual data using string variables and functions.",
     "slides": "lectures3/Pythonlearn-06-Strings.pptx",
     "chapters" : "6",
     "videos" : [
@@ -342,7 +342,7 @@
     "title": "Lists",
     "anchor": "lists",
     "icon" : "fa-list-ol",
-    "description": "We look at Python's simplest data structure - the list.  Lists can store more than one item in a variable.",
+    "description": "We look at Python's simplest data structure: the list.  Lists can store more than one item in a variable.",
     "slides": "lectures3/Pythonlearn-08-Lists.pptx",
     "chapters" : "8",
     "videos" : [
@@ -468,7 +468,7 @@
     "chapters" : 12,
     "anchor": "network",
     "icon" : "fa-cloud",
-    "description": "We take a quick look at how data moves acros the network using th HyperText Transport Protocol (HTTP) and ow we write programs to read data scross the network.",
+    "description": "We take a quick look at how data moves across the network using the HyperText Transport Protocol (HTTP) and how we write programs to read data scross the network.",
     "slides": "lectures3/Pythonlearn-12-HTTP.pptx",
     "videos" : [
         {
@@ -517,7 +517,7 @@
     "chapters": "13",
     "anchor": "servces",
     "icon" : "fa-briefcase",
-    "description": "Web services allow a program to access data available in a different server.",
+    "description": "Web services allow a program to access data available on a different server.",
     "slides": "lectures3/Pythonlearn-13-WebServices.pptx",
     "videos" : [
         {
@@ -582,7 +582,7 @@
     "chapters" : "14",
     "anchor": "Objects",
     "icon" : "fa-cubes",
-    "description": "We do a quick look at how Python supports the Object-Oriented programming pattern.",
+    "description": "We have a quick look at how Python supports the Object-Oriented programming pattern.",
     "slides": "lectures3/Pythonlearn-14-Objects.pptx"
 },
 {
@@ -692,7 +692,7 @@
     "chapters" : "16",
     "anchor": "dataviz",
     "icon" : "fa-bar-chart-o",
-    "description": "In this section, we learn to scrape data from the network, store the data in a database and then read the data from the database to produce in in-browser visualization of the data.",
+    "description": "In this section, we learn to scrape data from the network, store the data in a database and then read the data from the database to produce an in-browser visualization of the data.",
     "slides": "lectures3/Pythonlearn-16-Data-Viz.pptx"
 }