Constant (computer science)
A constant in computer science is a term used to describe a value or a literal that holds throughout a program’s execution. It is defined once, and usually cannot be changed thereafter. The opposite of a constant is a variable, which is a value that can change depending on the current program’s context.
Constants are commonly used in computer programming as they provide an easy way to store named values that may be referenced repeatedly throughout an application. Numeric literals, character strings, and other support data are declared as constants in order to facilitate a programmer’s task in performing certain repetitive calculations or operations. Additionally, constants provide a layer of abstraction between the code and the data of the programming project. By declaring the same values multiple times as constants, the logic of a program can be simplified, making it easier to understand and debug.
In many computer languages, declaring a constant involves the use of the keyword “constant”. For example, in the C programming language, a constant of the type “int” is declared as “const int my_variable”. Furthermore, some languages including Pascal, Julia, and Python, generally require the programmer to declare a constant as a single value, which cannot be modified thereafter.
In summary, constants are essential components of computer science. By providing an easy way to store named data, constants allow for more efficient programming and greater abstraction between the code and the data of the project.