A+: Printing technologies

 Printer mechanisms are mostly either Impact Printers (Daisywheel and Dot Matrix), Bubble-Jet (including Ink Jet) and Laser Printers. Less popular mechanisms include LED printers (Okidata's & Panasonic's less expensive / simpler equivalents of laser printers), solid ink printers (pioneered by Textronix before assimilated by Xerox) and dye-sublimation printers (slow, spendy and superb quality).

 Also, there are the ubiquitous thermal printers (cheap, but heat destroys the image so not used for anything you want to save, and the slick paper has toxic BPA in it).