I'm assuming you're driving a automatic tranny. It's called throttle response... But we would have to have more information about what you're experiencing... If it feels like the brakes are on when you release the gas pedal, then It could be a couple of things, including the fact that the car you're driving is pretty light and should slow quickly when you remove the gas...

If you're used to driving an SUV or some heavy POC car then that's your answer. The other thing is that you could be in some other gear aside from your primary drive gear...

But then again, we have no specifics on what you're experiencing.