A will written entirely in the testator’s handwriting and not witnessed.
Some states recognize holograph wills, other do not.
Still other states will recognize a will as "holograph" if only part of it is in the testator’s handwriting (the other part being type-written).
For example, Alberta recognizes holograph wills as set out at 7 of the Alberta Wills Act (RSA 2000 Ch. W-12, published at canlii.com/ab/laws/sta/w-12/):
"A testator may make a valid will wholly by the testator’s own handwriting and signature, without formality, and without the presence, attestation or signature of a witness."