The Officer is the most commonly simmed area of Star Trek. Which one might consider strange, as it is NCOs and Warrant Officer's that do the work. However the Star Trek series shows the main characters as officers, it is they that make the decisions in the end and you don't want to see a person take ages fixing one relay after another, so they are more interesting for TV. Here is the officer rank chart showing the order of promotion and the names of the ranks.

General
Brigadier General
Major General
Brigadier
Lieutenant General
Colonel
Major
Lieutenant Colonel
Marine Captain
1st Lieutenant
2nd Lieutenant
Cadet 4th Year
Cadet 3rd Year
Cadet 2nd Year
Cadet 1st Year