running 2 hard drives

I have my old primary hard drive with everything on it and I want to put in another hard drive because I'm running low on space. My problem is I don't understand how having 2 hard drives will work with one system. Is it a master/slave relationship where my old hard drive will still hold everything and the new is just extra storage? I'm confused.

Yeah you would just use master/ slave if your using ide.
If you have a serial ata drive there's no master slave setting.
And the hard drive you have now will still hold all the same information and like you said the new one will be extra storage.
hope this helps
-pies

Just plug it in!

If it a pata (ide) drive it will need to be set to slave with the jumper on the back and it will need to be pluged into the middle ide plug on the ide cable , when you boot to windows you will not see it under my computer if its a new hard drive, if thats the case right click my computer and left click manage go to disk management and you will see it there right click it and format after you have done that you should see it under my computer.

you can use it for extra storage and you can also install programs to it buy selecting the browse option and selecting to install to that drive.