In the prior two blogs I sped through over 300 years of technology evolution from scribes and clerks through the typewriter era. While I remember (not too fondly) typing papers for College on my Brother typewriter, even by my graduation in 1984, with the advent of the IBM PC and word processing software, high speed 24-pin dot matrix printers were becoming standard office tools and displacing typewriters. As early as the 1960’s, impact printers were pervasive in large computing centers. A number of technogies were available including line chain (IBM), drum (DataProducts), and line matrix (Printronix). These were the printers which used tractor fed ‘greenbar’ paper (if you know what that is, you are already dating yourself). Their little cousin, the desktop dot matrix printer didn’t really rise to prominence until the late 70’s and early 80’s.