Binary fission is the form of asexual reproduction in single-celled organisms by which one cell divides into two cells of the same size, used by most prokaryotes. This process results in the reproduction of a living cell by division into two equal or near-equal parts.
Mitosis is not the same as binary fission.

Process
Many organisms reproduce by binary fission, such as:
Some eukaryotes reproduce using binary fission-like methods. Mitosis is thought to derive from binary fission.

Bacteria
Archaea, such as Pyrodictium abyssi (an anaerobic thermophile of deep-sea hydrothermal vents)