why put a rickroll spoiler in your post are you 12 years old or something?
See, on forums, people have these things called "signatures" or "sigs". Thought they may appear to be part of the actual post, they're actually set beforehand, and appear under every post the user makes.
QUOTEOn web forums, the rules are often less strict on how a signature block is formatted, as Web browsers typically are not operated within the same constraints as text interface applications. Users will typically use a "signature" text area in their given profile for input, which can then allow a user to turn off signatures. Depending on the board's capabilities, signatures may range from a simple line or two of text to an elaborately-constructed HTML piece. Images are often allowed as well, including dynamically updated images (standard size 300x100pixels), usually hosted remotely and modified by a server-side script.
Signatures are seen as an art form by many of their creators, and there are many websites centered around their creation and display. Most of these websites have competitions, battles and a signature of the week contest, where members submit their entries to have them featured on the main page.