A real estate agent is a professional who helps people buy and sell properties. But there's more to it than that. Here's a primer on what real estate agents are (and aren't) and the different roles agents can take on in a real estate transaction.

Real estate agents are licensed professionals who facilitate real estate transactions between buyers and sellers. In a transaction, the agent representing the buyer is — no surprise here — the buyer's agent, while the seller's agent is often referred to as the listing agent. There are commercial as well as residential real estate agents; to buy or sell a home, you'll go with the latter.

Real estate agents on both sides of the transaction earn money through a commission, which is generally paid by the seller. Each agent's commission is a percentage of the total sale price, with the combined commission generally totaling 5% or 6%.

Real estate agents must be state licensed. In order to receive a license, agents generally undergo training and pass an exam. Continuing education is often required to maintain an active license. To verify that an agent is currently licensed, check your state real estate commission's website. You can also search the Association of Real Estate License Law Officials database website.

Agents may have additional certifications or accreditations that can be helpful when buying or selling certain properties. For example, if you're buying a condo, you might look for an agent who's a Certified Condominium Specialist. Someone who knows your area's developments and has experience with condo transactions may be an asset.

People often use the terms real estate agent and Realtor interchangeably, but that's sort of like saying Band-Aid when you mean adhesive bandage. Not all bandages are Band-Aids, and not all real estate agents are Realtors. (And yes, Realtor is a licensed trademark.)

A Realtor is a licensed real estate agent who is also a member of the National Association of Realtors. NAR is the largest trade association in the U.S., so many real estate agents are Realtors. Realtors are expected to adhere to NAR's standards and code of ethics, and they must participate in regular training to maintain their status.

NAR isn't the only trade association for agents. In addition to state and local associations, there are other national associations, including the National Association of Real Estate Brokers. NAREB, which emphasizes social justice and housing equality, designates its members as Realtists. Agents can belong to multiple professional organizations.

Real estate brokers are agents who've undergone more training and acquired additional licensing. Agents must work under a broker, but brokers may work independently or supervise real estate agents within a brokerage. With the brokerage model, the broker receives a portion of each agent's commission.

If you're interviewing a potential agent who is a real estate broker, ask whether you'll be working directly with them or be handed off to an agent within their brokerage. You may not want to go after a big-name broker only to find you'll mostly be working with their assistant.

You might also hear about discount real estate brokers. These are generally larger brokerage networks that connect home sellers with agents willing to take a lower commission. While it may cost less to work with a discount broker, there are trade-offs, as these brokers might not provide all the services a listing agent typically would.

Whether you're on the buying or the selling side of the transaction, your real estate agent will assist with several parts of the process.

Here's what you can expect any real estate agent to do:

• Have deep knowledge of the area. This can include property values and comparable home sales, but also information on schools, neighborhoods and more.

• Understand the process. The nuts and bolts of buying and selling are a given, but your agent should also know local and state real estate laws and common practices. They'll tip you off on who and what you'll need and when you'll need it.

• Answer all of your questions. If it's your first time buying — or selling — you're likely to come across terms you don't recognize and tasks that seem baffling. What's the difference between pending and contingent? Why do you need title insurance? How thoroughly do you need to fill out disclosure forms? Your agent should be able to confidently and competently explain it all.

• Take care of the paperwork. In some cases, your agent might be the one who draws up the contract. Even when that's not the case, an agent will usually review every document in the transaction. After you've signed off, the agent will submit the paperwork on your behalf.

• Keep lines of communication open. Buyers and sellers seldom meet (which is probably for the best), and your agent is your go-between. They will be in touch with the agent on the other side of the transaction and once an offer has been accepted, they will guide you through any negotiations. Your agent will also keep you (and the other parties) up to speed on where the process stands. Closing on a home can take a while, and it's easy to get antsy if you aren't sure what's going on.

• Provide support. Buying or selling a home is stressful, and a good agent will be helpful and compassionate. Whether you need a pep talk, a reality check or a shoulder to cry on, your agent should be there for you.

One more thing: Your agent should consistently represent your interests in the transaction. After all, getting the best price means two very different things depending on whether you're the home seller or the buyer. A single agent representing both sides is known as dual agency, and it's illegal in some states.