Geohelminths are parasitic worms that primarily inhabit the intestines of humans and animals, transmitted through contaminated soil. They include species such as Ascaris lumbricoides (roundworm), Trichuris trichiura (whipworm), and hookworms. These parasites thrive in warm, moist environments and can cause various health issues, particularly in regions with poor sanitation. Infection typically occurs when larvae or eggs are ingested or penetrate the skin.