The Top 5 JavaScript libraries/frameworks (unscientific comparison)

If the number of StackOverflow questions for a topic is taken as a criteria for a unscientific popularity contest, jQuery tops the list. Following are the total number of tagged questions for each topic at the time of writing:

• jQuery - 537253
• Node.js - 58212
• AngularJS - 57402
• jQuery UI - 29689
• jQuery Mobile - 19847

Node.js and AngularJS came much after jQuery but the general point is about which community is roughly larger & hence more popular.  If you put aside the religious wars, these numbers are helpful to decide if you should pick a particular library/framework over the other. It gives a rough estimate of the size of that technical community.

Of course, suitability to a specific task and a programming team's comfort with a technology is hugely more important than popularity. However, choosing the one with a large community can be beneficial especially with open source technologies for multiple reasons -
1) more people to seek help from if required
2) there is a lot of ready-made pre-tested code that can be adapted for custom requirements
3) influence future improvements to that library/framework.

Also see: The Top Programmers in India according to StackOverflow