> JQuery is a great example of how you can create a library with some core functionality and know with 100% certainty that if you use it correctly it will work

> JQuery is a great example of how you can create a library with some core functionality and know with 100% certainty that if you use it correctly it will work across all browsers that it was intended to support. Maybe 5 years ago. You cannot use modern JS and CSS in IE11, you need to use transpilers, polyfills and pray to god that all your dependencies are compatible. Testing and debugging is IE is slow and painful.