A headshot is an 8x10 photo, usually in color (but some actors still use black and white headshots), with the actors' name printed on the bottom and, if represented, the agency logo and information. A current resume of the actor's education and experience is attached to the back.
A composite or a zed card is 5 1/2 x 8 1/2 and used as a model's business card. It is in color and highlights the different "looks" the model has.
Headshot Printing on card stock
Headshot Printing on HD photo paper
Comp Card Printing on 14pt card stock