What is a fuser?

The fuser is the part of the laser printer that melts the toner onto the paper and makes it stick or "fuse" with the paper. The process is done with heat and pressure as the paper rolls through.
The fuser is possibly the most common part to fail in most laser printers.

Do I need a new Fuser?
Do you have marks on your paper that shouldn't be there after you print a page? Are they same on every page? You probably need a new fuser!
Is one side of the print faded or just a portion of the print consistently faded? Probably a fuser.