According to Michigan state law, a will is a document that appoints a personal representative. A will can also be a document that revokes or revises another will, a document that nominates a guardian, or a document that expressly excludes or limits the right of an heir to inherit the decedent's property. A will explains what the testator wants to have done with his (or her) property following his (or her) death.
Not every document expressing a testator's wishes is a will, though. While the document does not need to be in a particular format, it does need to be
Michigan also recognizes a holographic will as valid. In this case, the will may not be signed by witnesses but must be dated, signed by the testator and, for important provisions especially, in the testator's handwriting.
Laws change all the time, of course, but a will is valid at the time of the testator's death if it would have been valid on the date it was executed. Michigan will also recognize a will that was executed properly under the laws of another state or country if the testator owned a home there or was "domiciled" there. (Generally, domicile refers to someone's permanent home.)
A will may include a codicil -- that is, a legally executed document that revokes or amends part of the will. And, finally, a will may incorporate a separate writing by reference. For example, the will may state that the testator's jewelry is to be distributed in accordance with the Jewelry Distribution List. The list would describe each piece of jewelry and indicate who would inherit it.
Of course, it takes more than a writing and a few signatures to make a will valid. Validity also depends on the whether the testator can make a valid will. Who can make a will, however, is a subject for a future post.
Source: Michigan Compiled Laws Annotated, § 700.2501 et seq., "Wills, Will Contracts, and Custody and Deposit of Wills," via WestlawNext