Spiders have eight legs and fangs which generally inject venom. Spiders have amazing adaptations, such as camouflage, mimic ants, change the way they build webs and have suction - cup feet. Most spiders are solitary, and might even be aggressive to others in their species. Some will live in groups, though, which are called colonies. Most spiders will not harm you, but some will bite you if they feel threatened.