What it means in practice
The executor (called "personal representative" in some states) is the person responsible for shepherding the deceased's estate through probate, the court-supervised process of validating the will, paying debts and taxes, and distributing what's left to heirs. The job is meaningful work — typically 6 to 18 months for a routine estate, longer when there's real estate to sell or a business to wind down. The executor has fiduciary duties similar to a POA agent: they must act in the estate's interest, keep records, and not commingle funds. Most states allow the executor to take a fee (usually a small percentage of the estate); many family members waive it.
The distinction families most commonly miss: executor authority does not exist until death. A parent who has named you executor in their will has given you ZERO authority to act on their behalf while they're alive — to manage their finances during dementia, to talk to their bank, to handle their bills during a hospitalization, you need a durable power of attorney, not an executor designation. Discovering this distinction during a crisis (the parent is in the ICU, you have the will but no POA, the bank refuses to discuss the account) is one of the most preventable bad moments in family caregiving.
Many states allow simplified probate or small-estate affidavits when the total estate is below a threshold (typically $50,000–$200,000 depending on state). For estates large enough to require full probate, hiring an attorney is the standard play — DIY probate is technically possible but the procedural hazards are real.