You're probably seeing either retroarch or launchbox (or its full screen mode, bigbox)
Retroarch is an emulation suite that supports many systems, it has generally superseded many of the original emulators the various cores are based on
Launchbox is a front end that is pretty well polished, and so very popular
Most emulators have just been built/developed with what people are used to, or what they like, which has become more similar over the years. Your questions confuses me a bit, but if you are actually looking for a good front-end for your standalone emulators, try emudeck: https://www.emudeck.com/
Thanks. I was really just wondering why all the standalone ui's were so similar, which I think you've answered. I've heard of emudeck, but not tried it. Will give it a look
They’re all independent. There are other front ends that will add shine to the emulators like Launchbox or Emulation Station (desktop edition) if you find a list or just plain box art boring. Both have big picture mode for full screen.
I don't use windows but I heard of retrobat. Maybe that would work?
Community to talk about emulation & roms.
RULES:
1.) No bigotry
LINKS:
Emulation Wiki - Your source for everything emulation :)
[WIP] Emulation Links Wiki - My personal wiki for emulation links, please help contribute!
r/Roms Megathread - Megathread of Roms
RetroArch - RetroArch is the popular front-end to libretro which is a simple API that allows for the creation of games and emulators.