How many types of worm are there and what specif tpes are there?

There are three main types of worms: annelids (segmented worms), nematodes (roundworms), and platyhelminthes (flatworms). Annelids include earthworms and leeches, while nematodes encompass many species like Ascaris and Caenorhabditis elegans. Platyhelminthes feature species such as planarians and tapeworms. Each type plays a unique role in ecosystems and has distinct biological characteristics.