Most, if not all developers who read this have at least heard of jQuery, one of the most powerful Javascript libraries out there. Most notably, there are a seemingly infinite number of "plugins" or "packages" that can be downloaded and implemented with almost zero knowledge of coding.
As tempting as it may be to simply use a package deal, a little bit of jQuery knowledge can go a long way. Note that as a Javascript library jQuery isn't really a different language, it's an extension of Javascript that allows you to do essentially the same tasks with significantly less code.