A photocopier (which is also known as simply a copier, copy machine or photocopy machine) is a machine that can make paper copies of documents quickly and cheaply. Most current model photocopiers use a technology called ‘Xerography’. This is a dry copying process using toner and heat. Copiers can also use other output technologies, such as ink-jet, but xerography is the standard technology for office copying.

According to deanofficesolutions.com, the photocopier was officially invented in 1937 when inventor Chester Carlson invented a process called electron photography. Carlson ended up inventing the photocopier the same way a lot of things get invented — he wanted a more efficient way to complete an everyday task. 

Carlson’s job at a patent office required him to make large numbers of copies every day — which was expensive and difficult to accomplish at the time. 

For 15 years, Carlson worked on perfecting a way to transfer images from one piece of paper to another using static electricity. When he invented what he called "electron photography”, he filed a patent. 

It was almost one year to the date of the patent filing that Carlson created the first photocopy using the process that he later renamed to "Xerography”. 

Xerography garnered Carlson worldwide acclaim, as it was his invention that created the billion-dollar copier industry we know today. 

At first, according to photocopiers.net.au, Xerography was not a popular invention. It took 10 years for Carlson to find a company to develop his Xerography process. A New York-based photo-paper manufacturer, called The Haloid Company, finally took up the challenge. The Haloid Company later went on to become the Xerox Corporation.

In 1955, Haloid, by then called Haloid Xerox, had produced Copyflo, the first automated xerographic machine. But it wasn’t until 22 years after the process of electrophotography had first been invented that the first true office photocopier was produced. In 1958, the first-ever commercial push button plain paper photocopier, the Xerox 914, was introduced and ended up selling in the thousand’s.

In recent years, high-end photocopiers have adopted digital technology, with the copier effectively consisting of an integrated scanner and laser printer. This design has several advantages, such as automatic image quality enhancement and the ability to "build jobs” or scan page images independently of the process of printing them. Some digital copiers can function as high-speed scanners; such models typically have the ability to send documents via email or make them available on a local area network.