Innovations in operating software and in user-interaction made it easier to work with computers. The major software step was creation of the C programming language and a highly portable operating system called Unix capable of smooth data passing. The key interaction steps involved peripheral hardware and the human-machine interface to speed input of user commands. The leading contributor to this area, Douglas Englebart, led a group working at the Stanford Research Institute (now SRI International) . A key invention, the mouse, the computer-connected system for selecting a range of items or initiating actions rapidly by means of a single point-and-key-in (or click) operation, originated in that work in the sixties. Xerox started research on office technology in the seventies: their efforts led to presenting concepts through visual images. That idea is central to contemporary-computer graphic-user-interfaces (or gui): Apple's Macintosh and Microsoft's Windows 95 are both gui-based commercial products. Consider the following (italics indicate quotation) - here the first is from a world wide web page:
1. Two college dropouts, Steven Jobs and Stephen Wozniak, founded Apple in 1976 in the Santa Clara Valley. The original plan to sell circuit boards changed to selling fully assembled microcomputers after Jobs's first sales call brought an order for 50 units. They built the Apple I in Jobs's garage and sold it without a monitor, keyboard, or casing.
2. Both the Unix operating system and the C programming language are mainly due to the efforts of a few people. Ken Thompson was primarily responsible for the Unix system, a general-purpose time-sharing system that made it possible for many users to work on a single computer. Ideas and support from Rudd Canaday, Doug McIlroy, Joe Ossanna and Dennis Ritchie backed that development . Unix was the first operating system not written in assembly language, but in the C language. Brian Kernighan and Dennis Ritchie were the C developers.
There is a world of difference between Apple and Unix, since stand-alone and time-share are at opposite ends of the computer-use spectrum. Yet Apple, especially with the Apple II and the Macintosh, the pioneering commercial computer with a graphic user interface, broadened the appeal of, and market for, computers. Microsoft's Windows 95 gave IBM Personal Computers and their clones (PC's) graphic user interface ease-of-use via icons, point-and-click, mouse-driven commands. The fundamental kinship between Englebart-SRI/Xerox/Jobs-Wozniak-Apple and Thompson/Ritchie innovations was their focus on computer use.
Word processing grew out of using computers to store codes for alphabetic letters, numerals, and punctuation marks. Such software, capable of manipulating blocks of text, provides the easiest kind of computer use. Still much confusion arises when an unfamiliar word processing package must be used. No single thing creates the difficulty. The user's history (past use of other word processing software) causes reliance on shortcuts that may exist in the new utility. However the implementation could require initiating (essentially via keyboard actions) different commands.
 Johnson, J., Roberts., T., Verplank, W., Smith, D., Irby, C., Beard, M. and Mackey, K., "The Xerox Star: A Retrospective," IEEE Computer, Sept. 1989, 11-26.
 Kernighan, B. and Pike, R., The Unix Programming Environment, Englewood Cliffs, NJ: Prentice-Hall, 1984, vii-viii.