...of an idiot who doesn't know what things are. :S
Hmm, bit harsh? Maybe just a dunce. (hug)
jQuery neither prefixes variable names not puts dollars in front of selectors. It aliases itself as $, and as a function it can have arguments, the first of which can be a selector, though it also can be other things, and also has various methods attached to the function's object itself.
Which is not to say it isn't a bit dumb, but it is at least more convenient than typing case sensitive jQuery, though even that isn't as $durbrained $as $bloody $_PHP.