bash is a program and stands for Bourne Again SHell. This program takes a text file as input, assumes the text consists of instructions, and tries to process those instructions.
bin is a directory, also sometimes known as a folder.
If you are familiar with a Windows environment, "/bin/bash" in Linux would probably look more like "C:\bin\bash.exe" in Windows.
I've always assumed bin was short for binary, but everyone knows what happens when you assume.
Last edited by tnandy; 02-15-2006 at 10:04 AM.