Why use hex?

Question

Hey! I was looking at this code at http://www.gnu.org/software/m68hc11/examples/primes_8c-source.html

I noticed that in some situations they used hex numbers, like i

Answer 1

There are 8 bits in a byte. Hex, base 16, is terse. Any possible byte value is expressed using two characters from the collection 0..9, plus a,b,c,d,e,f.

Base 256 would be more terse. Every possible byte could have its own single character, but most human languages don't use 256 characters, so Hex is the winner.

To understand the importance of being terse, consider that back in the 1970's, when you wanted to examine your megabyte of memory, it was printed out in hex. The printout would use several thousand pages of big paper. Octal would have wasted even more trees.