Although people often use the terms interchangeably, there's a difference between an elder companion and a personal aide in terms of both responsibilities and training.
An elder companion, also
called a companion/homemaker, has less training than a personal aide. A companion prepares meals, does light housekeeping, and offers companionship. A companion may also help with laundry, do grocery shopping, and drive the older adult on errands. There are no training requirements for a home companion, but you want someone who's able to be caring and is a good personality match with the client.
A personal aide, also called a personal care assistant, may do all the same tasks as a companion but is also qualified to provide personal care, such as bathing, grooming, and dressing. Often a personal aide is required to have a home health aide certification, which involves competing a 76-hour, nurse-supervised training program.
Another difference is in scheduling. A companion can be hired for any combination of hours and usually works part-time. Sometimes companions are hired for just a few hours a week. A personal aide is more likely to work set shifts of daytime or evening hours.
One caution: When hiring someone, keep in mind that your situation is likely to change over time. Your loved one might be relatively healthy today and have a health issue tomorrow. If you anticipate hiring this person long-term, you might be better off with someone who has training and certification.