From a letter to an old friend to a bill sent to the electric company, mail is a large part of Americans’ lives. For many years, though, it was not recognized with anything as grand as a national museum. That changed 15 years ago when a small exhibit grew into the National Postal Museum that now sits at the corner of Massachusetts Avenue Northeast and North Capitol Street.

The museum, which opened in 1993, is celebrating its anniversary this year with a slew of special events and festivities culminating in a large celebratory exhibit in September.

“Prior to 1993, a minuscule portion of the Smithsonian’s postal operations and philatelic collections were on display, tucked away in a tiny corner on the third floor of the National Museum of American History,” Public Information Officer Meradyth Moore wrote in an e-mail. “We really needed to do better by this superb collection.”

Moore credits then-Secretary of the Smithsonian Robert McCormick Adams and then-Postmaster General Anthony Frank with playing major roles in the museum’s creation. She also noted that the museum’s first director, James H. Bruns, was instrumental.

Bruns “coaxed the museum into being,” with just a handful of staff members, she said.

One upcoming anniversary event will celebrate the first airmail flight that took off from New York on May 15, 1918. Visitors to “Adversity, Adventure and the 90th Anniversary of Airmail in America,” which will take place on May 15, will be able to check out the airmail exhibits and learn about the early pilots and aircrafts.

The celebration will culminate in September with a large exhibit entitled “Alphabetilately,” in which each letter will stand for some aspect of the stamp collection and mail. “From Advertising Covers to Zeppelins, each subject is introduced with a ‘non-Postage stamp’ image (called a Cinderella) designed for Alphabetilately by designers at 26 San Francisco Bay Area studios,” Moore wrote.

While the museum is happy to celebrate its past, it is also keeping an eye on the future with plans for renovations and new exhibits that will open over the next decade.

“The new exhibits will invite visitors to interact with the people around them and through online communities,” Moore wrote. “New exhibits will include a focus on postal employees, the roles of the post office in American society, history of military mail, the evolution of mail delivery from 1800 to the present, the business of mail, and finally, an exhibit that will examine the future of mail and the postal service.”