According to the Illinois Department of Health, tick color varies slightly by species. The lone star tick is a common brown-colored variety. People also tend to come across brownish-red ticks such as the American dog tick, black-legged or deer tick, brown dog tick and winter tick.
Ticks are not insects. They are classified as arachnids, like spiders, because they have eight legs and no antennae. Because they feed on the blood of animals, ticks are able to transmit diseases. A tick attaches itself to an organism and sucks blood for days. Common diseases that pass from ticks to their victims include Rocky Mountain spotted fever, Lyme disease, babesiosis (an infection of the red blood cells) and ehrlichiosis, which causes flu-like symptoms.