Star Trek "Duty Uniform" Engineering Dept.      Engineering/operations uniforms are worn by anyone who is involved in the maintanence of the ship, or any section which isn't command or the sciences. The Engineering/operations uniforms are a bright red shirt.
The Original Series was the first series of Star Trek, and as such, is the template for all later versions. Until the second movie, all the unforms seen were very similar in design. Following the movies, The Next Generation acted as a template.
Uniforms: Star Trek Uniforms: Duty, Engineering