Variable: Difference between revisions

Latest revision as of 17:25, 23 October 2025

A named container in a computer program where you can store, retrieve and change a value.

Details

Variables are like labeled boxes: you can store something inside, check what’s there, and update it. They make programs flexible by allowing you to work with data that isn’t known ahead of time.

Consider keeping track of a player’s score:

_{🤖 Pseudocode}

score = 0                   # store the initial value
score = 10                  # change the value
"Current Score:" score      # read the current value

A variable creates a space in memory called score to hold the player’s score value. This allows the game to update the score as it changes and display it to the player.

Before you can use a variable, you must first declare a variable in your program. You can also initialize it with a starting value, and once declared, you can reference it anywhere in your code to read or update its value.

Naming variables is surprisingly hard — and very important. A variable name is more than just a label; it communicates the purpose of the value stored in memory.

Poorly chosen names can make code confusing, difficult to read, and hard to maintain, especially in larger programs. Good variable names help both you and others understand what the code is doing at a glance.

Check Related Actions for details on how to perform different actions with variables.

Related Concepts

Has: Data Type
Used in: Variable Declaration
Used in: Naming Variables

Related Actions

Used in: Perform Arithmetic Operation
Used in: Check Odd or Even
Used in: Assign a Value to a Variable
Used in: Declare a Variable
Used in: Increment or Decrement a Variable
Used in: Print a Variable

References

Variable (computer science)

@@ Line 1: / Line 1: @@
 <span id="variablevariable"></span>
-A named place in a [[Computer_Program|computer program]] where you can store and change a value.
+A named container in a [[Computer_Program|computer program]] where you can store, retrieve and change a value.
 <span id="details"></span>
 == Details ==
-Variables are like labeled boxes: you can store something inside, check what’s there, and update it.
+Variables are like labeled boxes: you can store something inside, check what’s there, and update it. They make programs flexible by allowing you to work with data that isn’t known ahead of time.
-They make programs flexible by allowing handling values that change during execution.
 Consider keeping track of a player’s score:
@@ Line 16: / Line 14: @@
 <syntaxhighlight lang="console">score = 0                   # store the initial value
 score = 10                  # change the value
-"Current Score:" score      # use the current value
+"Current Score:" score      # read the current value
 </syntaxhighlight>
-A variable creates a space in memory called <code>score</code> to hold the player’s score.
+A variable creates a space in memory called <code>score</code> to hold the player’s score value. This allows the game to update the score as it changes and display it to the player.
+-----
-This allows the game to update the score as it changes and display it to the player.
+Before you can use a variable, you must first [[Variable_Declaration|declare a variable]] in your program. You can also initialize it with a starting value, and once declared, you can reference it anywhere in your code to read or update its value.
 -----
-To use a variable, we need to declare it first.
+[[Naming_Variables|Naming variables]] is surprisingly hard — and very important. A variable name is more than just a label; it communicates the purpose of the value stored in memory.
-Declaring a variable, consists of telling the program to reserve a piece of memory to store some data.
+Poorly chosen names can make code confusing, difficult to read, and hard to maintain, especially in larger programs. Good variable names help both you and others understand what the code is doing at a glance.
+-----
 Check [[#related-actions|Related Actions]] for details on how to perform different actions with variables.
@@ Line 35: / Line 39: @@
 * ''Has'': [[Data_Type|Data Type]]
+* ''Used in'': [[Variable_Declaration|Variable Declaration]]
 * ''Used in'': [[Naming_Variables|Naming Variables]]