A Trustee, Personal Representative, Guardian, Conservator, Healthcare Agent, and Power of Attorney are all legal roles that involve managing another person's affairs. The specific responsibilities and authority of each are different. So for your legal convenience, here's a brief explanation of each:
Trustee: A Trustee manages assets in a trust for the benefit of the trust's beneficiaries. The Trustee has a legal duty to manage the trust's assets according to the trust's terms and to act in the best interests of the beneficiaries.
Personal Representative: A Personal Representative (also known as an Executor or Administrator) is a person appointed by a probate court to manage the affairs of a deceased person's estate. The Personal Representative's duties include identifying and valuing the assets of the estate, paying off the decedent's debts and taxes, and distributing the remaining assets to the decedent's heirs according to the will or state law.
Guardian: A Guardian is appointed by a court to make personal and/or financial decisions for someone who is unable to make those decisions for themselves. Guardians are typically appointed for minors or adults who are incapacitated due to disability or illness.
Conservator: A Conservator is a person appointed by a court to manage the financial affairs of someone who is unable to manage their own finances. Conservators are typically appointed for adults who are incapacitated due to disability or illness.
Healthcare Agent: A Healthcare Agent is a person named by an individual to make healthcare decisions on their behalf should they become unable to do so themselves. Healthcare Agents are typically appointed through a healthcare power of attorney document. In Utah this is called the Utah Advance Healthcare Directive.
Power of Attorney (POA): A Power of Attorney is a legal document that grants another person (the agent or attorney-in-fact) the authority to make legal, financial, or healthcare decisions on behalf of the person who created the POA (the principal). POAs can be limited or broad in scope, and can be effective immediately or upon the occurrence of a specified event (such as incapacity). Really Good Wills packages include a POA that is immediately active for spouses to serve as power of attorney for each other, but contingent on incapacity for anyone else to have power of attorney. This power ceases upon the death of the person who created the document. It can only be used to manage assets in the individual’s name when they are living.
There is a bit of crossover between Trustees and Personal Representatives after someone has died, and crossover between Trustees and Powers of Attorney when someone is alive. However, these roles are often filled by the same person so it can be difficult to delineate where one power starts and ends.
In broad summary: