Comment BASIC on a TRS-80 clone (Score 1) 633
I first learn BASIC on a TRS-80 clone, then moved to my own ZX81 clone, where I started programming Z-80 assembly. After a few years, I upgraded to a MSX computer, where I learned Pascal and C.
The most important thing I learned was algorithms and data structures. BASIC in those three platforms are so different, that, unless you understood the algorithms, porting programs was not straight forward.