What It Is
A CNAME record, short for canonical name, says that one name is really another name. For example, www.yourbusiness.com can be a CNAME for yourbusiness.com, so both lead to the same place. Instead of pointing to a number, it points to another name, like a forwarding note that says to ask for a different person at the front desk.
Why It Matters for Your Business
Many online services ask you to add a CNAME so a subdomain on your domain points to their system. A salon might create book.smithsalon.com as a CNAME pointing to its booking provider. If that provider changes its servers, the salon does not need to update anything, because the CNAME follows the provider’s name automatically.
Good to Know
Under the standard DNS rules, the bare root domain (yourbusiness.com with nothing in front) cannot be a normal CNAME. Use an A record there, unless your DNS provider offers a special alias feature. Also, a name that has a CNAME should not have other records, such as MX, on the same name, because they can conflict.