Optimus Prime is an Autobot with the function of Commander.  He is “the largest, strongest and wisest” of the Autobots (according to his Tech Spec).  The main goal of Optimus Prime is to protect all life (including Earth-life) that his rival Megatron, leader of the Decepticons, seeks to destroy.

Optimus Prime transforms between his robot mode (transformed from the cab), truck mode (made up of cab and trailer) and combat deck (transformed from the trailer).

The original Optimus Prime was part of Takara’s Diaclone toy line in 1983 under the name “Battle Convoy”.  The Generation 1 Optimus Prime was then released as part of the Transformers by Hasbro in 1984.  The rub symbol did not come on the first year figures, it only appeared from 1985 onwards.