"What's in a name?" asked the Bard. "That which we call a rose/by any other name would smell as sweet."
Shakespeare and his star-crossed lovers notwithstanding, it matters to many when it comes to occupational titles. Thus, while anyone can claim to be a therapist in New York, massage therapists have to be licensed by the state in order to do business as such. But in the real estate industry, there are no such rules, aside from those already in place governing lawyers and accountants in general. Thus, many neophytes and laymen are often confused by the difference between a realtor and a real estate agent, and often confound the two, mistaking them to be one.
People often use the two words interchangeably, but there is a rather important difference between the two - at least as far as realtors themselves feel about it! For that difference involves credentials, and a realtor is accredited - though not by the state.
Realtors are accredited as such by the National Association of Realtors, a professional industry association that espouses a strict code of conduct for its members and holds them to it. Moreover, realtors typically have more training and more experience in the real estate business than does many a real estate agent. Though both a realtor and a real estate agent will need to be licensed, the realtor is required to go the extra mile in obtaining a further level of expertise by the National Association of Realtors. And so indeed, the term "realtor" is, in fact, an actual registered trademark.
But that's the only sure-cut difference, this matter of membership and what it suggests and is supposed to imply. Naturally, there are a great many good real estate agents out there who do a superb job every day serving their clients. But being a member of a professional association may give you, as the consumer, an additional venue if your experience be much less than satisfactory, one other than the usual governmental regulatory agencies.
However, real estate agents are also bound by a certain number of expressly legal obligations, such as preserving confidentiality, honoring fiduciary duties, and reporting all financial numbers. So the differences may not mean much, even on paper. To be sure, realtors have a little more education (or even a lot more, depending on your point of view), but you can also trust a real estate agent to help you sell or acquire property.
No discussion of this topic, however brief, would be complete without mentioning the widespread use of those non-licensed people who take it entirely on themselves to match buyers and sellers or, as is much more often the case, landlords and renters. These non-licensed people can usually be found online at sites like the famous Craig's List, and they certainly get business enough to keep them posting their listings day after day. And, especially when it comes to renting, people are loath to deal with real estate agents and brokers. What then?
Well, as many a free market economist might say, there's a buyer for every seller, which in our situation means that it all depends on what is needed. One can understand how if you're simply going to rent the second floor of someone's house you might not need a realtor. But when it comes to buying that person's house, a realtor is probably the way to go.