In 1976 semi-retired filmmaker and Altair programmer Michael Shrayer wrote The Electric Pencil Word Processor, the first word processing program for a personal computer. A character-oriented word processor program, Electric Pencil ran on a variety of machines including the Altair 8800, the Processor Technology Sol-20 and the NorthStar Horizon.
"Michael Shrayer purchased an MITS Altair computer kit after seeing the January 1975 issue of the Popular Electronics. He later expanded his Altair with a paper punch, video display, and keyboard and he began writing machine language programs.
"What became known as Electric Pencil started when Shrayer made some improvements to an editor assembler package called Software Package 1 or SP-1. He named his improved version Extended Software Package 1 or ESP-1.
"Shrayer decided he didn’t want to use a typewriter to write the documentation for ESP-1 but to use his Altair instead. There were no suitable programs available, so he decided to write his own. As he stated in an 1984 article in Creative Computing:
" 'I developed the original Electric Pencil to document something called ESP-1. At that time, I didn’t even know that a product like Pencil was
called a word processor. In fact, Electric Pencil was the first word processor ever written for a microcomputer. I used Pencil to document
ESP-1 and then itself' "(http://www.trs-80.org/electric-pencil/, accessed 9-2020).