Hasbro, co-operating with Takara, aimed to bring various products from their lines into one unified line for international release, featuring robots that change their physical form to become all new vehicular entities, and needed ways to promote them for the American consumers. Marvel Comics were brought in to make a comic book series about them, and also assisted in providing character information, back stories and tech specs for them, but something more was needed for it to be a hit. Something more accessible.
An animated television show.
As the totally rad intro explains, the Autobots are heroic robots who can transform into cars (plus some who become a space shuttle and a few dinosaurs) that fight the evil Decepticons, who are always on the lookout for energy to manifest to either return to their home planet Cybertron, defeat the Autobots or simply rule the universe. They're also a varied bunch, ranging from jets, a camera, insects, giant pistols, cassettes and a boom box, yet no matter what devious scheme they're up to, the Autobots are always there to put a stop to it.
Beginning with a three-part story arc involving the Transformers' arrival to Earth, it continues on episodically with another three-parter towards the end, but generally maintains consistency throughout events of the series; if Megatron is blown up and trapped in space or something, then the Decepticons will naturally be in disorder the next episode until he just comes back and takes order again, refusing to explain how exactly he survived being caught in the explosion of hundreds of violently combusting energon cubes, the energy source he planned to use to destroy the Autobots forever. This distinguishes it from the second season, where the action is completely episodic with no continuity, meaning bad guys immobilised by a frenetic device in one episode will be good as new during their next attempt for power. Which, ultimately, isn't much different from Megatron surviving so many mishaps, but play the game, son.
I think it goes without saying that it was a successful venture, and the series went on for two more seasons plus a feature-length movie, along with Japanese spin-offs and other media, creating simple little characters that captured the hearts of the audiences all over the world. Still a successful franchise to this day, you could say that it transformed the audiences' views on robots and cars eh wot eh wot wot
You shouldn't have let me write this, Galv'.