Carps are a type of fish.
Like all types of fish, each carp gives one fish fillet when caught.
Carps can be caught in medium and small circles and therefore are harder to catch.
See Fishing List for more detailed information.
Carps in the fishing book
The carp is on page 18 of the fishing book:
The teddy bear of the lake. He's big, cute and huggable and would never hurt another fish.