What does javascript use?

Is _javascript client or server side processing?

For example, if I had a lot of _javascript on a page, does it stress the client computer or my server? I think it's the client but I'm not sure.

The reason I ask is if I wanted to dynamically filter something, but I didn't want to stress my server, I could pass the items to the cilent and have them filter it and display the result to themselves. But this won't work if _javascript uses MY cpu.

Javascript is client side. It stresses the client computer. It also helps to have the _javascript in a whatever.js file and then reference it from the page that uses it.

JavaScript can be client-side and server-side.

JavaScript traditionaly is embedded in the Web Browser of the client, so this is client-side. There isn't that much processing involved, so I wouldn't worry too much.

Also, in the last few years JavaScript is being used embedded in other enviroments such as ASP (Active Server Pages) and ASP.NET. This is server-side, so it's down to the server to do the processing.