I know there was website I once saw that permitted me to play interactively with JavaScript and jQuery. It had an IDE, a render pane and a result debugger thing too.
Does anyone know what it was called or anything like this?
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Sign up to join this communityAnother option besides jsFiddle is jsbin.com. You can even save your experiments under a public URL, so that others can view and edit your creation.
If you're using Firefox, install FireBug, and then FireQuery.
Then on any webpage, open FireBug (bottom right), and enable the console (should be a little down arrow by "Console"). From here you'll see a button "jQuerify". Clicking it will inject jQuery into the current page.
You can type whatever jQuery-dependant JavaScript you want into the command-line.
If you are using FireFox you can use the FireBug Add-On.
If you are using IE, you can use the Developer toolbar (For IE7 or earlier you have to download and install it separately)
Press f12 on either platform to activate it. There is a Javascript console in lets you interactively enter java script commands.
It's not a web app, but take a look at jQueryPad. It's a downloadable application you can use to quickly build and test your script and markup.
javascript:alert('hello');