PS1 roms help

i just started using roms and emulators a little whie ago.....is there emulators that u can just download the games off the internet and play them????cause the only emulators i keep downloading are the ones that u can only put in a ps1 cd for it.....and i dont got no ps1 cds.....and also please tel me a GOOD site that i can download the ps1 roms at...thanks

please read the rules. We cannot provide you with any copyrighted files. PS1 games are not roms. They are called ISOs or cd images since they are a lot bigger.

I feel pretty dumb...wat are ISOs?