Did you know that the fax machine was invented before the telephone? Alexander Bain invented the first fax machine in 1843; Alexander Graham Bell, the inventor of the telephone, didn't even start working on his first phone until the 1870s.
How fax works
Bain's fax machine translated telegraph signals into images on paper. Fax machines have worked pretty much the same way since the beginning. And while the first faxed pictures weren't photo-quality, the basic idea — the coding and transmission of images — remains the same today.
A modern fax machine scans an area of an image and reads the space as either white or black. Each color is either a 1 or a 0. On a traditional fax machine, these "numbers" are transmitted as alternating tones over a phone line. The coded document is then "read" and "drawn" by the fax machine on the receiving end. With Internet fax, these numbers are transmitted as packets of data, just like data over the internet. That's all there is to it.
Growth of Commercial Fax
Commercial fax machines didn't take off until the 70s and 80s. Although fax technology was authorized for civilian use in 1948 (previously, the military closely guarded fax technology), it took twenty years for the industry to develop. Fax machines, apparently, have always been temperamental, and you had to have the exact same model of machine to transmit documents from one machine to another. In 1968, the Consultative Committee for International Telephone and Telegraph (now the International Telecommunications Union) solved this communication problem. It mandated the first industry standard for fax machine transmissions.
Once the format was standardized, the growth of fax machines was inevitable. Not only did costs drop, but exploding telephone service expansion meant that the market for faxing grew along with it. In addition to the growth of the telephone network and the customization of that faxing format, there were two important contributors to faxing's growth: Japan and the newspaper industry.
In Japan, it was faster to handwrite a document than to type it — it took a little bit of software innovation to allow all 10,000 characters or so to be typed quickly. So, Japanese businesses turned to fax machines for quick communication. That's why Japan was the first country to develop a massive fax machine market.
Newspapers also used fax machines, even before they were cheap, to transmit images to different newsrooms around the globe. They also used their fax lines to solicit stories and receive other photographs. Many faxing milestones were established by newspapers before 1968.
In 1985, GammaLink produced the first computer fax board, called GammaFax. In the mid-nineties, various not-for-profit services pioneered unreliable email-to-fax and fax-to-email services. The fax industry splintered. Now, the majority of faxing is done online, by for-profit email-to-fax services. Investment and technology development have allowed Internet faxing's functionality to grow — and become cheaper and cheaper.
Faxes continue to be used heavily today, but through a variety of methods: traditional phone lines, radio fax, computer faxing, VoIP faxing, and Internet faxing. Whatever faxing service you use, it will transmit your documents cheaply and when you want.