How to learn computers

I seem to have received this question with increased frequency lately: "How did you learn so much about computers?"

I guess first, you'd have to have some idea of what I do know about computers.
Here's a condensed list of what I know:

• I know how the internet works
• I understand how 1s and 0s are converted into useful programs
• I can program
• I know what a machine is doing while you're waiting for it to boot
• I usually know what a program is doing when you get an hour glass
• I know everything that can be known about the windows OS without having the source code available--from design, to internal workings
• I know most of the internal workings of Linux
• I am comfortable with most types of unix-based operating system

So, how did I learn all that? I've thought a lot about how to answer that, and here it is:

Mess around

That's it. I'm not scared of my machine. I've never been scared of losing my pictures or music or anything. I backed them up onto a CD if I thought they were important, and then just dug around and started changing things in the computer to see what they would do. I've broken it--but even that isn't a big deal, as it only takes 8 clicks (15 if it's windows) and about 30 minutes of waiting (up to 2 hours in windows) to wipe the computer clean and start again fresh. The longer you do that, the more proficient you'll be with you computer. Treat it as a toy--not as a tool, and then beat it up and play with it.
It, sometimes, helps if you know what you want to do with your computer. I typically wanted them to play games--but I eventually moved onto wanting to do fancy server-side stuff. If you're willing to experiment with your machine--you'll quickly discover what it can do. Just don't be afraid of anything on it, and there's no limit to how much you can learn.

So, there. I learned computers by messing around.