Reserved Word
Reserved words (occasionally called keywords) are one type of grammatical construct in programming languages. These words have special meaning within the language and are predefined in the language’s formal specifications. Typically, reserved words include labels for primitive data types in languages that support a type system, and identify programming constructs such as loops, blocks, conditionals, and branches.
The list of reserved words in a language are defined when a language is developed. Occasionally, depending on the flexibility of the language specification, vendors implementing a compiler may extend the specification by including non-standard features. Also, as a language matures, standards bodies governing a language may choose to extend the language to include additional features such as object-oriented capabilities in a traditionally procedural language. Sometimes the specification for a programming language will have reserved words that are intended for possible use in future versions. In Java, const and goto are reserved words — they have no meaning in Java but they also cannot be used as identifiers. By "reserving" the terms, they can be implemented in future versions of Java, if desired, without "breaking" older Java source code. Reserved words may not be redefined by the programmer, unlike predefined functions, methods, or subroutines, which can often be overridden in some capacity. The name of a predefined function, method, or subroutine is typically categorized as an identifier instead of a reserved word.
Read more about Reserved Word: Reserved Word Vs. Keyword, Comparison By Language, Reserved Words and Language Independence
Famous quotes containing the words reserved and/or word:
“We know of no scripture which records the pure benignity of the gods on a New England winter night. Their praises have never been sung, only their wrath deprecated. The best scripture, after all, records but a meagre faith. Its saints live reserved and austere. Let a brave, devout man spend the year in the woods of Maine or Labrador, and see if the Hebrew Scriptures speak adequately to his condition and experience.”
—Henry David Thoreau (1817–1862)
“Hardly had the glow been kindled by some good deed on your part or by some little triumph over your rivals or by a word of praise from your parents or mentors when it would begin to cool and fade leaving you in a very short time as chill and dim as before.”
—Samuel Beckett (1906–1989)