When linking to webpages, if the URL contains any unusual characters, such as spaces, you need to escape the URL. To escape it, paste it in the top left box, and press the escape button. This should appear in the top right box, for your use. To unescape an address, use the bottom set of boxes instead. The initial http:// does not need escaping. Encode and Decode skip over this.
2.0 adds more stuff for added value! The Base64 stuff won't work in all browsers, but provides special bonus powers! See also the coder tool (for ROT13, XOR, and more!)