To be a hacker you have to understand what hacking means. In a nutshell to hack is to be inovative, try nre things, think outside the box. Hackers would reprogram things to do different tasks. With that said you have to find an objective before you decide what to learn. If you wanna do web hacking then you should start with common web languages like HTML, PHP, CSS. Learn how to build from the groud up before you try to infiltrate. By doing that you'll pick up flaws and loop holes. So before even dreaming about SQL injections or about defacing a website or rooting a server learn how to build a website, that is the best place to start. Hacking is not only a hobby, it's a whole community and a culture. G4E has excellent information on the subject about the history of hacking and techniques, methods, etc. Look around and I'm sure you'll find great stuff. AND ASK QUESTIONS!
“There are no foolish questions and no man becomes a fool until he has stopped asking questions”
Overall. HAVE FUN!