After I've put songs on my ipod from a cd, can I delete the songs from the computer to save space or will it then remove them from my ipod the next time I plug it in?
...unless you delete the files from the PC (using windows explorer) but leave them in the itunes library. The songs will have an exclamation mark next to them in itunes to show that it can't find them, but they won't get deleted them from the ipod.
Hammer is quite correct, if you simply delete the files but don't remove them from your library they will not be removed from the iPod, but by doing it that way you will end up with a messy iTunes library with lots of songs that will not play listed in it.
Have you considered getting an external hard drive to store your library on, then you won't have to worry about deleting stuff to save space.
you can not delete the songs from the itunes if you will delete the songs than the yellow exclamation sign will come up when you synchronize the songs with the ipod to the itunes. and the songs will not play.