In Factorization, we talked about Euclidean domains and unique factorization domains. In this section, we introduce another class of integral domains called Bézout domains. As the name suggests, Bézout domains are integral domains where the Bézout identity holds. They are also a generalization of principal ideal domains.

Bézout Domain

A Bézout domain is an integral domain such that the sum of any two principal ideals is again a principal ideal.

e.g. Clearly any principal ideal domain is a Bézout domain. In fact, the converse is also true: any Bézout domain is a principal ideal domain. This can be seen from the following proposition: