Being a REAL programmer (C, C++) I have a good knowledge of binary, octal and hexadecimal counting systems. Assembly language was (and still is) fun. But I got into all this in the early 80s because I could see electronics (I started life as a radio/TV tech) was turning to rubbish as the throw away junk started showing up. My first 'computer' was a home made thing you programmed via a hex keypad and used a 6805 processor. They were the days when men were made of steel and ships of wood and small furry creatures from Alpha Centauri were real small furry creatures from Alpha Centauri. Oh, and I loved valves - my first homemade amplifier was a valve amp, massive 3 watts per channel (two 6bm8s and a 6x4).