You can build many useful web apps with just a few files. You can also extend this simple notes app to add more functionality ...

Valve has reportedly fixed an HTML injection flaw in CS2 that was heavily abused today to inject images into games and obtain other players' IP addresses.

CSS: Enter CSS to be applied to the HTML used in your tests. It is placed between <style> elements in the header portion of the page. HTML: This area allows you to enter HTML to be used in your tests.