In military service, a commissioned officer has responsibility for the training, readiness, and supervision of units. In contrast, noncommissioned officers (NCOs) have that responsibility for individuals.
Rank titles vary significantly between armies and navies, and sometimes air forces. There are, of course, national variations not just in the native language phrasing of a rank, but in the number of rank levels used by a particular country.
Officer grades break into three rough "bands":
10. Admiral of the (Navy or Coast Guard)
9. Vice Admiral
8. Rear Admiral Upper Half
7. Rear Admiral Lower Half
6. Captain
5. Commander
4. Lieutenant Commander
3. Lieutenant
2. Lieutenant Junior Grade
1. Ensign