Firefox seems to automatically decode URLs. Not a bad thing, but it's important to know! Developers encode URLs to pass data between internet applications through URLs because not all data passes well (an easy example is the Carriage Return character). I was working on a single sign-on web application by copying and pasting generated data into a second application; however, I failed to realize the errors in the second application came from Firefox decoding my safely encoded data. I actually switched to IE in order to get the proper values.