What are 'betta' or 'Siamese fighter' fish?

What are 'betta' or 'Siamese fighter' fish?

Marc Grover (Professional Aquarist) gives expert video advice on: Why aren't male bettas kept in the same tank?; Can I put a betta in my aquarium with other fish?; Where is the best place to put my betta? and more...

Anabantid is what the actual name of a betta fish is - the type of species that it is. It is an unique fish, most of them come from Thailand the orient Siam. They typically live in the wild in small muddy pockets of water - think rice patties. They call them fighting fish because the males will fight each other to the death. You don't want to put two males together.