In the early days of the mainframe computer users input programs and data using things called punched cards. They would submit these in stacks to operators for feeding into the computer. The processed outputs would then be returned a day or two later either on punched cards itself or later on sheets of paper.
Studied under the field called Human-Computer Interaction (HCI), the way people interact with computers has changed dramatically in the past four to five decades. Some of the inventions leading to this are:
* The Keyboard *
Owing its origins to Christopher Latham Sholes’ 19th century QWERTY typewriter keyboard, the electronic version increased the speed, efficiency and accuracy where it came to data input to computers. People could also perform great new features such as Backspace and Delete to correct their typographical errors immediately!
* The Monitor *
By the mid-sixties a quantum leap in visualizing computer programs and data was taking place. Video Display Terminals (VDT) based on the cathode ray tube started to become commonplace and could display text so users could immediately see what they were inputting to the computer and what the computer was outputting back to them. This was the era of the text based computer terminal.
* The Graphical User Interface *
The next stage of computer display evolution after the text terminals was sparked by the invention of the graphical user interface (GUI). The paradigm was simple- to display visual output in a rectangular piece of real estate on the screen called the Window- one that could be created or destroyed at will. This “window” could also be interacted with using not just the keyboard but other devices such as the mouse. This phenomenon interestingly emerged from the labs of Xerox at the Palo Alto Research Center (PARC) but was made omnipresent through the now famous Windows operating system.
* The Mouse *
Output and input capabilities have always needed to be sync. Thus, as the GUI evolved and became capable of displaying fairly rich information including text, imagery or a combination of both, demands were also placed on how people could input information better into the computer. This led to the invention of the wheel mouse in the late ’60s and then the common ball mouse in the ’70s (which also interestingly emerged out of the labs at Xerox PARC).
* Touch Screens *
In modern times there has been a trend to merge the input and output capabilities of computers leading to hybrid devices such as touch-screens. Instead of using a mouse and pointing at a location on the screen to click, one can simply touch that location directly on the screen. This mode of input though has become far more popular in the mobile space far than it has with normal desktop or laptop computers, although that is poised for change.
Research in the area of Human-Computer Interaction is active and as a result, inventions continue to grow. Sound commands and speech-to-text capability for input through microphones, camera-based eyeball tracking devices, text-to-speech software for accessibility, tactile interfaces such as static and vibrations joysticks and foot pedals and even the use of brain wave forms for automatic input are but a few of the inventions that are transforming this exciting landscape. From humble beginnings, a whole new world now lies ahead.
Human Computer Interaction on Wikipedia: http://en.wikipedia.org/wiki/Human%E2%80%93computer_interaction
A Brief History of Human Computer Interaction from CMU: http://www.cs.cmu.edu/~amulet/papers/uihistory.tr.html