Insects (Insecta) are a class of arthropods characterized by a three-part body (head, thorax, abdomen), compound eyes, antennae, and three pairs of jointed legs. They inhabit diverse environments, from forests to deserts, playing crucial roles in ecosystems as pollinators, decomposers, and prey for other animals.

Insecta is not a single species but rather a class in the animal kingdom that includes a vast number of species. Insects are found on every continent, including Antarctica (though in very limited numbers), and inhabit nearly every terrestrial environment. They are the most diverse group of animals, with millions of identified species spread across the Earth.

Insects occupy a wide range of habitats due to their adaptability. They can be found in deserts, forests, grasslands, wetlands, mountains, and even urban areas. Their environmental conditions vary widely: some are adapted to dry, arid climates, while others thrive in humid, tropical environments. Certain species are aquatic and can be found in freshwater and marine environments.

Insects play crucial roles in ecosystems as pollinators, decomposers, and as a food source for other animals. They occupy various ecological niches, from herbivores to predators and parasites. Their adaptability allows them to exploit a wide range of food sources and environmental conditions, contributing to their evolutionary success and diversity.