Electricity is absolutely, positively nothing to fool around with. Treat it with the respect it deserves. If you’re thinking about working with anything that is related to electricity it is very helpful to have a basic understanding of what it is and how it works. Here is a pdf from NYU Engineering that explains the basic concepts in a clear manner:
You don’t need to know everything the article talks about but it will give you a good understanding of what electricity is and why you need to show it the respect it deserves.