I still love the world of computer programming, even though I have wandered away from it to some extent. When I began, purchasing the huge, comprehensive and often very expensive programming language texts was the best way to learn. However, the Internet and many generous authors have changed all that.
A great resource that provides free technical tutorials is freetechbooks. There are some excellent full-text manuals here that would help anyone interested in learning various areas related to programming or computer science.
Also, if you already have a good programming background and just need a refresher or ‘cheat sheet’, these ‘quick reference cards’ would be very useful for just about any programmer.