If you cracked the screen (the glass part) of your cell phone, can it be replaced?

If the glass part of your cell phone screen gets cracked, can you buy a new piece of glass (I’m not sure if it’s glass or plastic) to replace it? I went on ebay and typed in nokia 6030 replacement screen but I think it just brought up the types of screens that go under the glass. Everything is still working just fine but the glass is cracked.