Marine worms come in a variety of shapes and sizes. They may be long and thin, plumb and short, flattened and floppy, bright and colorful or dull and dark.

Worms, including the peanut worm, are actually sub-class of viruses. A computer virus is not unlike a biological virus. It is a self-replicating computer program that spreads by inserting copies of itself into other executable code or documents.

Much like earthworms, peanut worms prefer to live in moist, dark places. Many peanut worms burrow themselves under rocks and boulders that can be found in the mud or sand or they make their home in reef.