Most people use one of two kinds of computer printer:
A laser printer works by projecting an image of the page it intends to print onto a rotating drum. This drum has a special selenium or photoconductive coating that attracts laser toner particles when charged with electricity. The toner is stored in a laser cartridge, and rolled directly onto a piece of paper. The printer then applies heat to melt the toner, which is made up of a special type of plastic, onto the sheet. As soon as a laser print dries, it's waterproof and resists abrasion.
The first laser printer was invented by Gary Starkweather at the Xerox company in 1969, and the first networked version appeared in 1971. By 1975, IBM had invented the first commercial printer, a room-sized device called the Model 3800. This printer was used only for high-volume document printing, like invoicing, and wasn't available for the average consumer.
Office printers came onto the scene in 1981 with the Xerox Star 8010. This printer was very expensive, and most people never saw a laser print until the first HP LaserJet appeared in 1984. The LaserJet cost about $3,500 and had trouble with high-resolution graphics, but it used a conventional toner cartridge and worked much like a modern laser printer. This device was much larger than the printer on your desk today, however.
Since the advent of the consumer printer, both laser toner and printers have become much less expensive. In fact, just about every home and commercial office has one. Similar technology is used in photocopiers, with some models offering both copier and printer functions. There's a healthy market in third-party accessories, too. You can choose a laser toner cartridge manufactured by the same company that makes your printer, a remanufactured cartridge from that company or a third-party toner catridge at a discounted rate. Some people even refill their own toner cartridge, which can be messy and risky, but saves even more.
If you've never bothered to think about your laser printer, take a moment to appreciate it. In this age of easy, crisp, attractive prints, it's hard to remember a time when we had type everything on a manual machine, and when making another copy meant a lot of work. Your laser printer supports a whole range of industries, provides durable, readable prints, and keeps your office running smoothly, day after day.