A more thorough explanation:

A joint will is a legal document that is executed by two or more testators, usually a married couple, to dispose of their common property by transferring their separate titles to one devisee. It is also known as a conjoint will.

For example, a husband and wife may execute a joint will that leaves all their property to their children after both of them pass away. In this case, the will is executed by both the husband and wife and is considered a single document.

The joint will is different from a mutual will, which is two separate wills in which two persons establish identical or similar testamentary provisions disposing of their estates in favor of each other.