Many versions ago you got an Operating System user's guide with the software. I keep this manual with me always because it is an invaluable source for finding information on scripting and commands, and is still reliable even though it was written for version 3.2.4.
Unfortunately, if you can't find a copy of this manual you will need to go to the man pages, which do contain the information you are looking for, just not in print.
Try any of the following, depending on whichever shell you are scripting in.
man sh - for bourne-shell
man csh - for c-shell
man ksh - for korn-shell