Manual typewriters were complex and intricate machines. Other than the keys, there would seem to be no comparisons with today’s keyboards and screens. But evolution always carries along a legacy of earlier forms.
A typewriter had a “carriage” that held the paper between rollers. The paper could be fed up and down, and the carriage could move left and right so that letters and digits would be placed along a line of text. There was a big lever sticking out on the left; it was called the “carriage return”. When your typing came close to the right margin, a bell would ring, signaling that you had five letters to go; you’d better finish the current word or hyphenate it. Then you would push the carriage return lever, which fed the paper up one line, and moved the typing location back to the left margin of the paper.
All the little levers that held the letters were mounted together on a base that could be shifted up with the “Shift” key. When up, a capital letter hit the paper; when down, a lowercase letter. The mechanism could be raised and locked in position with the “Shift Lock” key.
To erase, either you backspaced over the mistake and typed Xes over it, or you rolled the paper up and painted over the mistake with “whiteout”.
To underline a word, you backspaced to the beginning of the word, then typed the underscore character under each letter.
Margins and tabs were mechanical stops that you set by hand.
With the advent of electric typewriters, and then computers, typewriters and typing evolved. And, just as in biological evolution, wherein changes are dependent upon the incremental modification of existing forms and features, there is a traceable legacy of old forms and features in modern keyboards and typing.
Electric typewriters produced the line feed and carriage return with the touch of a new key, labeled “Return” instead of the big lever; there was still a bell to tell you to finish the current line. Of course you still had to press keys, but the long, resistant stroke was reduced to a short, easy touch. The mechanical noise of each keystroke was still there.
When typewriters were attached to computers as “terminals” or “consoles”, typing had to go in two directions: from the typewriter terminal to the computer, and from the computer to the terminal. Thus, signals were devised to instruct either end of this connection as to what was typed or was to be typed. The instructions are called “character codes” or a “character set”. These character sets included, and still include, codes for carriage returns, line feeds, and even a bell.
Surprisingly, typewriters used a lowercase “l” for the digit “1”, and a capital “O” for the digit “0”. (You can see why.) Typing habits had to change subtly, but critically.
Referring now to the latest keyboards, we can still see subtle legacies of the manual typewriter. The “Backspace” key backs up, but now erases as it goes; it now is labeled “Delete”. Whiteout is no longer necessary, but the word is used to describe a zero-visibility snow storm, or even used metaphorically to denote an official cover-up of crimes, as in the book “Whiteout”, by Alexander Cockburn.
We no longer backspace and overtype the underscore to underline a word, but the underscore character persists. There is no carriage to “return”, but the “Return” key is often used to signal the end of a unit of input, so it now tends to be labeled “Enter”.
The use of the bell has changed from warning about impending line ends (words now automatically “wrap” to the next line) to signaling when you have tried to type some odd character in the wrong place. (There was a time when the bell rang to tell you that you had pressed the “Return” key!)
One of the most remarkable changes is invisible most of the time: the available character set has expanded from only a few dozen symbols to tens of thousands. You can now type along in English, switch to Russian, then to Armenian, then Gujarati, then Chinese, and so on, each language displayed in its own writing system. This Unicode character set has replaced the limited, Western-oriented ASCII character set.
And now the iPad has replaced the physical keyboard with a picture of a keyboard. You type by touching the images of the various keys. But there is “one more thing” that has been retained, perhaps for nostalgic reasons, or as reassurance that you have touched the key, or perhaps even to let you know that there is someone in the next room typing: the clicking sound that we all associate with typing.