In TOS
Gold – Command
Blue – Science and Medical
Red – Engineering and security

A lot of the time if a red shirt person unknown character went on an away mission, they usually got killed.

In TNG, i think the same for voyager and DS9

Red – Command
Blue – Science and Medical
Gold – Engineering and security

In TNG DS9 Voyager

Red –> Command (Janeway/Picard)
Blue –> Science and Medical (The Doctor/Dax)
Gold –> Engineering and security (O’Brien/Data)

In Enterprise I think it may be close to the same…
Red –> Command
Blue –> Science and Medical
Gold –> Engineering and security

but Im not quite sure, they only have little stripes of colour so I may be wrong