If you are up for a little pop quiz, and you have a Facebook account, visit the “News Feeds” page and make a list of everything on the
page that you consider to be using AJAX.

This is a bit of a trick question. How many items you find depends on how granular you try to be.

Below is my own quick attempt. I tried to be as granular as possible without spending all day on it. My purpose behind doing this is to point out just how much is going on in that page without even leaving the page or refreshing. This is an excellent example of how interactive a true modern web application can be.

Note that I subscribe to the Wikipedia definition of AJAX.

Feel free to add anything I missed in the comments.


Friends Requests menu
- User profile image
- Name
- Count of mutual friends
- Confirm/Deny buttons
Messages Menu
- User profile image
- User name
- Message snippet
- Message time
Notifications Menu
- User profile image
- User name
- Notification type icon
- Notification time
- Notification icon shows updated notification count
Search
Options Menu
- Count of new notifications for Pages
Live Feed/Contact Bar on the right
- Feed updates realtime
- User image, name, update snippet
- Mouseover a live update provides a popup
- User image
- Name
- Full update content
- Like button
- Make comment
- Timestamp
- Security
- Popup has an options menu
- Comments from friends with timestamp, like link, like count
- Contacts update realtime
- Profile image, name, and online status
- Search
- Options menu items
- Live chat with other user
- Video chat with other user
- Chat menu
- Typing status
- Video and Close buttons have popup with explanation
Left Nav
- Section Headers are links that update page content without refresh
- Edit menu for each navigation item
- Notification count for certain nav items
- Create Group button pops up dialog
- Members list auto-completes as you type
Right Nav
- Current birthdays
- Todays Birthday, popup, that allows you to comment and multiple walls at once without leaving the Feed page
- People You May Know
- Profile image
- Name
- Count of mutual friends
- Menu of mutual friends
- Friend list assignment menu
- Add friend
- Remove friend suggestion, new friend suggestion replaces it
- Sponsored Story
- Like button
- Remove story
- Sponsored Ad
- Some ads can popup in page like video and picture and everything that goes along with that
- Remove ad menu, new ad replaces it
News Feed
- Update status on page
- Who are you with feature
- Location feature
- Security menu
- Add Photo/Video on page
- Ask Question
- Poll options
- Security
- Sort menu
- Sort menu options
- New Stories
- Count of new unseen stories
- Load new unseen stories
- Friend updates
- Update options menu
- User image
- Name
- update content
- like button
- comment inline
- share feature
- timestamp
- location
- security, also has popup explanation
- list of friends who liked
- count of comments, names of friends who commented
- count of shares
- Comments
- commenter image
- commenter name
- commenter comment
- commenter timestamp
- commenter like button
- post a comment inline
- Scrolling to page bottom loads more updates