i need help obd2 or obd1?

I know i should know this by now bu i was wondering what is the difference beween obd1 n obd2? I feel pretty stupid asking but im still trying to learn as much as i can. Any info would b appreciated.  

im pretty sure it has to do with years bu not sure wich ones if it is.  

its all smog testing its the emissions of your car generation.. they get more strict each year  

indeed.. your supposed to have the obd that was made for your car or higher. or at least thats how it is here in cali.  

obd1 is for cars 92-95
obd2 is for cars 96-98
then you have some cars like the civic the the 98 is obd2A and the 99 civic is obd2B. But like he said its all in the emissions of the car.  Obd1 usually has 1 O2 sensor where as the obd2 has 2 or more.  Obd1 allows you to get more power out of the engine.  taht why you alsways see peopleing doing the swap from 2 to 1.  

In your opinion which Odb works best for a engine swap, a Honda Odb or an aftermarket Odb?  

not to flame you or anything but do you do swaps yourself? cause obd is kinda something you should know.  

like hero said bout doin motor swaps here in PA also you can put motors in whatever as long as the obd is the same or better... and before you do a motor swap def know what obd your current car is so you can get a motor of the same generation or better to make the wiring easier and of course so you dont spend that money then get a kick in the gut when you have to take an obd-0 motor out of an obd-2 car .. that would be a waste of time and money  

no i dont but i understand i shuld, but the best way to learn is to ask, thanks for all the help.