Annulment is a legal procedure for declaring a marriage null and void. Unlike divorce, it is usually retroactive, meaning that an annulled marriage is considered to be invalid from the beginning almost as if it had never taken place (though some jurisdictions provide that the marriage is only void from the date of the annulment. In legal terminology, an annulment makes a voidable marriage null. If a marriage is void ab initio, then it is automatically null, although a declaration of nullity is required to establish this. The process of obtaining a declaration of nullity is similar to an annulment process.