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It is, however, probably still wise (and certainly polite) to include the URL from which you got something as a comment in your code.
My childhood was spent on DOS and Windows 95. After learning to read, I managed to learn the basics of programming with the help of The Secret Guide to Computers, GWBASIC, UCBLogo, LADYBUG Logo, and some LOGO book(s) I can't recall the names of. I didn't much like GWBASIC, but at least it had a printed reference manual. I had also tried QBASIC, but had trouble with the online help, which I later decided was probably because all of the text was in the same font (making it hard to tell the verbatim code from the other notation).
[... Windows, VB, DJGPP, Cygwin, Mindstorms, POV-RAY ...]
Eventually I bought my own computer and installed a copy of Linux, and that's when I really began to learn how computer systems work: technical documentation for most things was available online, and if that wasn't enough to satisfy my curiosity I could look at the source code.
[... Python ... Haskell ...]