Difference between revisions of "Variable"
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* [https://en.wikibooks.org/wiki/Computer_Programming/Variables Computer Programming/Variables]
* [http://openbookproject.net/thinkcs/python/english3e/variables_expressions_statements.html Variables, Expressions and Statements (Python)]
* [https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/var C# Var]
Revision as of 17:28, 7 June 2019
- 1 Definition
- 2 Relevance
- 3 Explanation
- 4 Resources
In programming, a variable is comprised of:
- a storage location (identified by a memory address)
- an identifier
- value (a known or unknown quantity of information)
As the name variable implies, information may change as the program executes. However, its name, type, and location often remain fixed.
A Compiler will replace a variable's identifier with the data location.
scalar: an alternative term for a variable.
An identifier is the name used to reference either the the stored value or the variable itself; the variable's name can be used separately from the data it represents.
Changing the type of data stored in a variable may change the way the data can be used. For example, in most programming languages two integers added together will produce a sum that is also an integer.
a = 1;
c = a+b; // c will be 3
However, if a is a string (such as "hello"), adding it to an integer would not necessarily provide you with an integer as a result.
a = "hello";
c = a+b; // c will be hello2