Originally Posted by seypat

The scale of improvements/changes are perceived differently by different people. The bicycle used by riders to go off the pavement has evolved dramatically. But on the road side, mostly refinements. Derailleurs/multiple gears was a big development. Shifters moved around and eventually settled on the handlebars as the preferred choice. Braking is going from rim based to discs. Frame/ components materials have changed/evolved. Along the way, with each development, the bike has got more gears, or less gears. With each development, the bike has become lighter, or heavier, more aero, or less aero. It's become more user friendly, or less depending on who's talking about it. By and large, more or less, it's the same "safety bike" that replaced the Penny Farthing. The one thing that hasn't changed at all, at least on BF, is people arguing/discussing every possible aspect about it. Time marches on.

Edit: I forgot about bikes that aren't human powered or assist the user. Even those aren't new. They've been around for generations. They just went by different names like mopeds.