Active and Passive Voice: When you are active, you do something. When you are passive, things happen to you. This is the same concept as the active and passive voice in sentences.
In the active voice, the subject performs the action described by the main verb. In the passive voice, the action described by the main verb is done to the subject.
Example 1a, active voice: "The service team collected the parts."(subject: service team; main verb: collected)Example 1b, passive