I slept good last night.
Yes, I know that proper English should be "I slept well last night."
But, as Kev says, I live in Kansas, and we don't have to speak proper English in Kansas.
So, I slept good.
You know what good means...
I slept all night long, didn't wake up once, and woke up refreshed, feelin' great.
Now think about it, when you sleep well ...well, that's different than sleepin' good. Isn't it.
When someone asks if you slept well, you will, more than likely, say yes.
And the word well encompasses a wide variety.
I can sleep well at a hotel, but I can't sleep good at a hotel.
See the difference?
So, last night, I slept good.
How 'bout you? Did you sleep well last night?
Or, like me, did you sleep good?