I have not seen a dot matrix printer in use in 5 years. There might be some hipster retro person that loves their Epson but I don't know any. Businesses that used multi-part forms were the last place I knew of that used dot matrix printers.
The technology by which an image (letters are also images) is imprinted onto a paper is vastly different between laser and matrix printers.
- laser printers deposing micro-sized particles from a reservoir onto the paper, and paper then goes thru a furnace to fix the image;
- matrix printers use a set of micro-hammers (usually, nine or 24) to strike ink-soaked ribbon over the paper.
@Kane - Last time I've visited Kragen / O'Reily, they still used OKI's on dual-ply paper.