jQuery is a great library and it helped me a lot in starting to like web development. Abstracting away all the typical Javascript problems and giving a nice syntax instead, it makes web development fun again.
Of course learning jQuery still requires some investment from your side, you still need to understand HTML, Javascript and CSS. To help you learn jQuery Rebecca Murphey wrote a free book about the jQuery Fundamentals.
A must read for all web developers and a resource to keep close to you.