You may think that spiders and ticks are insects, but they are not. They belong to a group of animals called arachnids. Unlike insects, arachnids have eight legs instead of six and do not have antennae.
Besides spiders and ticks, other arachnids include scorpions, daddy longlegs, and mites. Arachnids live throughout the world. There are about 60,000 known species (kinds) of arachnids. The largest ones are found in warm climates.