Centipedes are long, multi-segmented arthropods that resemble millipedes.  Centipedes have only 1 pair of legs on each segment, while millipedes have 2 legs on most segments.  Centipedes also resemble insects, but insects have only 3 body segments and 6 legs.  Centipedes have 1 pair of antennae, and chewing mouthparts.  Centipedes are unique because their first pair of legs have evolved into venomous fangs.

Centipedes have incomplete metamorphosis: young centipedes hatch from eggs and look like small adults. Centipedes shed their skin (a process called "molting") as they grow into adults. Some species add legs each time they molt.

Most centipedes live underneath rocks, fallen logs, and in soil and leaf litter.  Centipedes are primarily carnivorous, and they feed on crickets, worms, termites, ants, and other small creatures.  Centipedes use their venomous front legs to capture and paralyze their prey.  Most centipedes hunt at night and hide during the day.  Centipedes are sometimes eaten (especially when they are young) by spiders, predatory insects, other centipedes, and insectivorous mammals and birds.

SCOLOPENDROMORPH CENTIPEDES
ORDER: Scolopendromorpha
Other than the house centipede, the most familiar centipedes in Kentucky may be the Scolopendromorphs (order Scolopendromorpha).  Full-grown scolopendromorph centipedes have more than 21 or 23 pairs of legs.  Pictured below are some common scolopendromorphs.

Hemiscolopendra marginata
ORDER: Scolopendromorpha | FAMILY: Scolopendridae | GENUS and SPECIES: Hemiscolopendra marginata
Hemiscolopendra marginata is probably the largest centipede found in Kentucky.  It can reach 3".  They are commonly found under logs and loose bark.

Scolopocryptops sexspinosus
ORDER: Scolopendromorpha | FAMILY: Scolopocryptopidae | GENUS and SPECIES: Scolopocryptops sexspinosus
Scolopocryptops sexspinosus is common under rocks, logs, and loose bark in Kentucky.  This vivid red-orange centipede can reach 2-3".  The molting centipede pictured in the Life Cycle section above is also probably S. sexspinosus. And visit this Bugguide link to see an incredible image of S. sexspinosus guarding a clutch of eggs.

Look for most centipedes underneath logs, loose bark, rocks, mats of dead leaves, or inside rotten wood.  Scolopendromorph centipedes are especially common underneath loose bark on fallen logs.  House centipedes are very common in many homes and buildings in Kentucky, especially in garages, sheds, and similar locations.  If you are interested in collecting a centipede, never pick one up with your hands; instead, "herd" it into a container with a stick or forceps.  Centipedes are best preserved in alcohol.

If you are brave (and careful!) enough, you can try to keeping a centipede as a pet in a small container.  Provide a few inches of potting soil, and some rocks or wood to hide under. The soil should be kept fairly moist.  Feed centipedes living insects or worms that are about ¼" the size of the centipede.

Centipedes also make interesting photography subjects, but they are so fast-moving that it can be hard to get a picture.  Make sure to use a fast film speed in bright light.  Another trick: before a photo session, cool down a centipede in a refrigerator for about 15 minutes.  The centipede will recover fully in a minute or so after it is removed from the cold, but it will move slowly in the meantime - just enough time for a few good pictures.

Some centipedes are incredibly large.  Giant centipedes from South America will grow to over a foot in length.  For a large centipede like this, insect aren't much of a meal: instead, prey include mice, snakes, lizards, and frogs.

Centipedes have different numbers of legs depending on the species.  Although the species with the most legs look impressive, the fastest centipedes are often the ones with the fewest legs (such as house centipedes).

Centipedes and millipedes are believed to be more closely related to insects than to spiders and other arachnids.

For more information about scolopendromorph centipedes, including the geographic ranges for common species, visit the North Carolina Museum of Natural Sciences website here.

It is often said that centipedes have "100 legs." Although the word "centipede" means "100 legs," centipedes usually have much fewer legs, around 30-50.  Some species of soil centipedes can have over 300 legs.