Japanese motorcycles during the 1970s all looked extremely similar. Honda defined the design, and rivals closely emulated it. The Honda CB750 essentially created the segment, with the Kawasaki Z1 hot on its heels. Then there was the Suzuki GS750. Unlike its rivals, it didn't set the world on fire when it came out. What it did, however, was improve on its rivals' successful designs to become an even better motorcycle.
The GS750 came out in 1976, seven years after the introduction of the CB750 and four years after the Z1. Suzuki's engineers had plenty of time to study the competition and design their own variation on the theme. They built an engine that so closely resembled Kawasaki's, they changed the design of the cam covers specifically so it wouldn't look like they ripped off the design.
Suzuki didn't rip off the competition, though. They improved on it. Somehow, despite using what appeared to be the same forks, the GS750 handled much better. Where the CB750 and Z1 had some noticeable frame flex, the Suzuki was rigid, inspiring more confidence in the corners. It had twin disc brakes, which were eventually introduced to the CB750 but not immediately. It even had an indicator to tell you what gear you are in, something even most modern motorcycles don't have. The GS has had it as standard equipment since the 1970s.
I have a particular attachment to the Suzuki GS series. My first bike was a GS650L, followed by a GS550E that I rode for many years. Later I restored a GS1100L that had struck a moose (it's a thing in Maine, where I lived at the time), including wiring up the replacement gauge cluster's gear indicator so that it worked again. As a still somewhat new rider, that final GS scared me with its power. It was the same engine that would become the basis for the GSX-R line of sportbikes. The more entry-level GS500 would continue in production all the way to 2013, giving the GS line a healthy 37-year run. This GS750 is where it all began.