jQuery Forum

The first one you have there looks like an anonymous function is being created that will let you use the $ inside of it as you would in regular JQuery code. Is that from code that is also using another scripting language that uses the $ in it?

The last two lines are essentially the same thing just written two different ways. It is the JQuery ready handler: http://docs.jquery.com/Tutorials:Introducing_%24%28document%29.ready%28%29

It is not a problem to have more than one of them in your code, either in the same file or over multiple files: http://docs.jquery.com/Tutorials:Multiple_%24%28document%29.ready%28%29  If you want to condense your code you can just take everything that is inside either of those two blocks and put them all in the same one, you'll need to be careful to get them in the same order though or you could run into problems.

Dave