I am going to be doing a digital art project with some artists and would like some explanation on the bleed margin.

I looked up the definition online and I think I know what it's referring to. In regards to doing something in photoshop for example, lets say a page with a gradient overlay on it, that fills an 8.5 x 11 inch document, or a standard pag size. There is always a white border when I print it out on photo paper.

With that said I'm guessing the bleed margin is that space that is removed if I have a professional printer, print the pages, is that correct?

If not, can someone explain the advantages and disadvantages of the Bleed Margin?

Thank you,

Invision