Line matrix printer
A line printer's speed with a dot matrix printer's freedom: an oscillating bank of hammers that dots the full page width one row at a time.
Instead of fixed type, a row of hammers rides a shuttle that swings a few millimetres sideways, over and over. The paper advances one dot row at a time while the hammers strike the ribbon wherever ink is wanted. Because the image is built from dots rather than cast characters, the machine can print any typeface, graphics and — the part that matters commercially — barcodes, while keeping line printer throughput of several hundred to over two thousand lines per minute.
Printronix in California introduced the technology in 1974 and still lives off it. That a 1970s impact technique is on sale in the 2020s comes down to two things a laser printer cannot do: it prints through carbon copies in multipart forms, and it keeps working in the dust, damp and heat where toner and a fuser roller give up.