High Quality Content by WIKIPEDIA articles! The line printer is an impact printer in which one line of text is printed at a time. They are mostly associated with unit record equipment and the early days of digital computing, but the technology is still in use. Print speeds of 600 lines-per-minute (approximately 10 pages per minute) were achieved in the 1950s, later increasing to as much as 1200 lpm. line printers print a complete line at a time.line printers have speeds in the range 150 to 2500 lines per minute.the different types of line printers are drum printers and chain printers.