Can someone give me a brief run down of Pre(After)-Market Trading?

[bigbet1234]

From what I gather is. If you want to buy in pre/after you have to put a "offer" in. lets say stock XYZ you put a limit order in for 100 share at 10.50 a share, if someone accepts, you purchase the stock? Is that right?

Also, let's say at 1am on Tuesday, I put a limit order in for XYZ at 10.50 a share, will that share be available in Pre-Market at 8am EST?

Thanks,

BB