I was wondering if there is a reference guide telling you of all the variables like %c for the time and %h for computer name

If anyone could tell me where to find such documentaion then that would help alot

For what software? Are you looking to customize your prompt? If that's the case, then all of the escape sequences (what you're referring to as variables) are described in the man page for the shell. For instance, if you're using bash, then there's a section entitled "PROMPTING" that will list all the possible things you can put in your prompt. If you're talking about the tcsh shell, the sequences are listed under the prompt entry for "Special shell variables".

If you're not talking about any of those, then we'll need to know specifically what you're trying to accomplish and/or where you are using them.

i am talking about kde logon screen, but i am taking it that it uses the same variables as bash does