FLAT CUT OUT

As simple as it sounds. Made of plastic or aluminum and are routed out cut. It can be painted or just raw aluminum looks and may depends on how complex your logo signs can be. Attachment to walls would be one of the easiest to work on. Most will choose this type of signs because it is simple, cheap, and also can be outdoor and indoors as well. 

Perfect for non illuminated signs and smaller in sizes especially with texts.