My father bought me a used Sinclair ZX Spectrum+ from someone who couldn't figure what to do with it, when I was 11. The succinctly written manual that came wi

My father bought me a used Sinclair ZX Spectrum+ from someone who couldn't figure what to do with it, when I was 11. The succinctly written manual that came with it had I all need to master BASIC, followed by learning to program in machine code straight (no assembler!) by age 14. It would be hard to say what would have been if this had not happened. This machine had me figure several things well ahead of my age, including coordinate geometry, computer graphics and animation, compilers and interpreters, computer architecture and basic logic design, et al. One thing I could not figure from the manual was the meaning of functions "sin" and "cos"! The latter was pretty much the only area where school helped. :-) I still have the machine, and sometimes miss that 16 kB of ROM'ed machine code that could do so much for its size.