Binary fission "division in half" is a kind of asexual reproduction. It is the most common form of reproduction in prokaryotes such as bacteria. It occurs in some single-celled Eukaryotes like the Amoeba and the Paramoecium.
In binary fission DNA replication and segregation occur simultaneously. In binary fission, the fully grown parent cell splits into two halves, producing two new cells. After replicating its genetic material, the parent cell divides into two equal sized daughter cells.