Roaches are insects of the order Blattaria.This name derives from the Latin name for the insect, Blatta.

There are about 4,000 species of cockroach, of which 30 species are associated with human habitations and about four species are well known as pests

Among the best-known pest species are the American cockroach, Periplaneta americana, which is about 30 millimetres (1.2 in) long, the German cockroach, Blattella germanica, about 15 millimetres (0.59 in) long, the Asian cockroach, Blattella asahinai, also about 15 millimetres (0.59 in) in length, and the Oriental cockroach, Blatta orientalis, about 25 millimetres (0.98 in). Tropical cockroaches are often much bigger, and extinct cockroach relatives such as the Carboniferous Archimylacris and the Permian Apthoroblattina were several times as large as these.

Roaches do bite, soo if your like sleeping and such they do bite you, other than that they leave you alone.

Steps on how to kill Roaches =\

1. Find out if you have cockroaches. Cockroaches (see picture) are generally medium-sized insects, although in some parts of the world they can get quite large. They have spiny legs and long antennae. If you see even one roach, you've undoubtedly got a lot more. The problem is they generally hide during the day, so you may need to look for them at night with a flashlight. Even if you can't find any of the insects, check cupboards and pantries for their droppings -- tiny brown slime stains or pellets.
2. Try to figure out where they're coming from. If you see cockroaches, try to follow them to figure out where they go. This is easier said than done, however, so you might need to do a little sleuthing. Check all around the house for cracks and holes through which roaches may enter. Roaches often enter through drains or vents, so you can't seal up everything.
3. Kill the roaches. There are a variety of do-it-yourself options for killing cockroaches.

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