Back in June der Mouse <mouse@Rodents.Montreal.QC.CA> wrote:
: This was 10base5.  (As I understand it, the 10 is the bit rate,
: megabits per second; the "base" stands for "baseband"; and the 5 has
: something to do with the cable, but I'm not sure what - fuzzy memory
: says it's the maximum cable length in hundreds of metres.)

'5' is the diameter of the cable in tenths of an inch.  10base2 was
much smaller, a little under a quarter of an inch.

Warner