Relation btw commands, "man" and "more" ???

Hi guys,
Hope u r doing find. I have this query. When we check the manual pages for a certain command, say

man cat

we see the manual page with

more

What is UNIX really doing here, I mean why not less command instead of more command. And can we have UNIX display the manual pages with less command instead of more command, or within the vi editor? And where are the manual pages stored within the filesystem, and are they simple ascii text?
And one more question, when we set our EDITOR environment variable to a certain editor, say vi, what does that basically mean. What does the default editor really mean, and where does that affect us?

man man :).

Specifically, check how it uses MANPAGER/PAGER.

It always helps to know what Operating System and version you have. Solaris and Open Solaris are quite different when it comes to "man".

The pager used by the "man" command is influenced by external environment variables.
See:

man man

On your question about EDITOR (or more usually VISUAL).
On most Solaris platforms this is explained in:

man 5 environ

One place where setting EDITOR is critical is before running the unix "crontab" command. The absolute default editor is the ancient "ed" text line editor program.

When writing scripts for the user world, you can set PAGER to a suitable pager program with parameters which disable the "!" Shell breakout feature.