¿Qué es un insecto?: insectos por doquier

Insects are ubiquitous, living in diverse environments across the planet. With over a million known species, they are the most abundant animals on Earth. While some insects, like bees and wasps, can sting and cause allergic reactions, most are harmless. Common misconceptions about insects being dangerous are addressed, highlighting that many are interesting and beautiful.

How many known types of insects are there approximately?

What are some characteristics of most insects according to the text?