Why process forms with jQuery?

We use forms on the web to get input from our users. Sometimes we send that input to a server to save it, and sometimes we just do something interesting with it in the browser. We often use jQuery to help us process that form, either before sending to a server, or replacing the need for a server entirely.

We can use jQuery to do form "validation" - checking that inputs are the correct format, like the right phone number or length - and then send it off to a server. We do form validation in a few places on the Khan Academy settings page:

We can also use jQuery to create an in-browser quiz or game, like the exercises we have on Khan Academy:

You'll use the same techniques for both of those sort of uses, and that's what we'll go through now. If you need a review of HTML forms first, go through these slides.

Note: Due to a browser bug, form processing won't work in IE 11 in our Khan Academy webpage environment. Please use a different browser if you're currently in IE 11.