The automated teller machine, or ATM, is such a complicated piece of technology that it does not have a single inventor. Instead, the ATMs we use today are an amalgam of several different inventions. Some of these proto-ATMs dispensed cash but did not accept deposits, for example, while others accepted deposits but did not dispense cash. Today’s ATMs are sophisticated computers that can do almost anything a human bank teller can, and have ushered in a new era of self-service in banking.

The Early Days of Automated Banking

Many experts believe that the first automated banking machine was the creation of an American inventor and businessman named Luther Simjian. Simjian held patents on all kinds of things–including an army flight simulator, a color x-ray machine, a self-focusing camera, an exercise bicycle and a teleprompter–but he was best known for his work on the Bankograph, a machine that could accept cash or check deposits at any hour of the day or night.

Did you know? Even extremely remote areas are serviced by ATMs–there are two in Antarctica.

In 1960, Simjian managed to persuade a New York City bank to take a few of his automatic-deposit machines. So that customers could trust that they would see their money again, there was a microfilm camera inside the Bankograph that took a snapshot of every deposit. Customers received a copy of the photo as their receipt. Still, the Bankograph did not catch on. “The only people using the machines were prostitutes and gamblers who didn’t want to deal with tellers face to face,” Simjian explained, and there were not enough of them to make the machines a worthwhile investment.

The Advent of the ATM

By the end of the 1960s, however, times were changing, and a broader segment of the population–more comfortable with the idea of self-service and more willing to trust unfamiliar technologies–was willing to give automated banking a try.

In 1967, a Scottish inventor named John Shepherd-Barron was sitting in the bathtub when he had a flash of genius: If vending machines could dispense chocolate bars, why couldn’t they dispense cash? Barclays, a London bank, loved the idea, and Shepherd-Barron’s first ATM was installed in a branch on Enfield High Street not long afterward. Unlike modern ATMs, Shepherd-Barron’s did not use plastic cards. Instead, it used paper vouchers printed with radioactive ink so that the machine could read them. The customer entered an identification code and took her cash–a maximum of £10 at a time.

The first automated banking machine in the U.S. was devised by a Dallas engineer and former professional baseball player named Donald Wetzel. Wetzel’s machine used plastic cards like the ones we use today. (Instead of radioactive ink, the cards stored account information in magnetic strips.) In September 1969, a Chemical Bank branch on Long Island installed the first of Wetzel’s machines.

The Spread of ATMs

By 1970, dozens of U.S. banks had jumped on the ATM bandwagon. To introduce this new machine to consumers, banks used all kinds of advertising tricks. For example, to get the attention of female customers, a bank in Columbus, Ohio, sponsored a six-hour Paul Newman movie marathon on a local television channel. Every 25 minutes during the movies, commercials for the bank touted the advantages of its new cash-dispensing machine.

However, it took a corporate gamble and a blizzard for the ATM to win the confidence of American consumers. In 1977, the chairman of Citibank took a huge risk, spending more than $100 million to install ATMs all over New York City. That investment paid off the following January when a huge blizzard hit New York, dumping 17 inches of snow on the city. Banks were closed for days; meanwhile, ATM use increased by 20 percent. Within days, Citibank had launched its by-now-familiar “The Citi Never Sleeps” ad campaign. Posters and billboards showed customers trudging through snow to get to Citibank ATMs.

After that, almost every one of the country’s banks followed Citi’s lead. The era of the ATM was underway.

ATMs Today

Today, there are almost 2 million ATMs around the globe. Although use of the machines has declined in recent years, likely because more people make purchases using credit and debit cards instead of cash, the ATM continues to have a place in modern culture. Today’s machines sell everything from airline tickets to movie tickets to medicine.