A typewriter is a mechanical or electromechanical machine for writing in characters similar to those produced by printer's movable type by means of keyboard-operated types striking a ribbon to transfer ink or carbon impressions onto the paper. Typically one character is printed per keypress. The machine prints characters by making ink impressions of type elements similar to the sorts used in movable typeletterpress printing.
The slash ( /), also known as a stroke and by the technical term solidus, is a sign used as a punctuation mark and for various other purposes. It is often called a forward slash, a retronym used to distinguish it from the backslash ( \). It has many other names.
ASCII ( ), abbreviated from American Standard Code for Information Interchange, is a character-encoding scheme (the IANA prefers the name US-ASCII). ASCII codes represent text in computers, communications equipment, and other devices that use text. Most modern character-encoding schemes are based on ASCII, though they support many additional characters. ASCII was the most common character encoding on the World Wide Web until December 2007, when it was surpassed by UTF-8, which includes ASCII as a subset..
In computer programming, a parameter is a special kind of variable, used in a subroutine to refer to one of the pieces of data provided as input to the subroutine. These pieces of data are called arguments. An ordered list of parameters is usually included in the definition of a subroutine, so that, each time the subroutine is called, its arguments for that call can be assigned to the corresponding parameters.
In mathematics, especially in set theory, a setA is a subset of a set B, or equivalently B is a superset of A, if A is "contained" inside B, that is, all elements of A are also elements of B. A and B may coincide. The relationship of one set being a subset of another is called inclusion or sometimes containment.
