72 lines
1.9 KiB
Markdown
72 lines
1.9 KiB
Markdown
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---
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title: Variables
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---
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## Variables
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# Creating (Declaring) PHP Variables
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Variables are "containers" for storing information.
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**Syntax:**
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```php
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<?php
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$txt = "Hello world!";
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$x = 5;
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$y = 10.5;
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?>
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```
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After the execution of the statements above, the variable $txt will hold the value Hello world!, the variable $x will hold the value 5, and the variable $y will hold the value 10.5.
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##### Note: When you assign a text value to a variable, put quotes around the value.
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##### Note: Unlike other programming languages, PHP has no command for declaring a variable. It is created the moment you first assign a value to it.
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# Rules for PHP variables:
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* A variable starts with the $ sign, followed by the name of the variable
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* A variable name must start with a letter or the underscore character
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* A variable name cannot start with a number
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* A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )
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* Variable names are case-sensitive ($age and $AGE are two different variables)
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# Output Variables
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The PHP echo statement is often used to output data to the screen.
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The following example will show how to output text and a variable:
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````php
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<?php
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$txt = "github.com";
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echo "I love $txt!";
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?>
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````
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The following example will produce the same output as the example above:
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````php
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<?php
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$txt = "github.com";
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echo "I love " . $txt . "!";
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?>
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````
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The following example will output the sum of two variables:
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````php
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<?php
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$x = 5;
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$y = 4;
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echo $x + $y;
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?>
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````
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# PHP is a Loosely Typed Language
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In the example above, notice that we did not have to tell PHP which data type the variable is.
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PHP automatically converts the variable to the correct data type, depending on its value.
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In other languages such as C, C++, and Java, the programmer must declare the name and type of the variable before using it.
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#### More Information:
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<!-- Please add any articles you think might be helpful to read before writing the article -->
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