in photography a print made by laying the negative on the photographic paper and exposing with white light.
Normally, a piece of heavy, flat glass is put on top to guarantee negative flatness.
A contact print does not use an enlarger: a bare 45 Watt bulb is more than enough for the task.
Contact prints are usually done as a quick-and-dirty way to see (more or less) what the photograph looks like
Proof sheets are usually contact prints. In large format work, the contact print can actually be the finished product.
Notice that the platinum printing process can only produce contact prints, which is why you rarely see very big platinum prints.