What does variable mean in php

Variables in php are "containers" used to store information. Similar to algebra, PHP variables can be assigned a certain value (x=5) or an expression (z=x y); the variable can be very short names (such as x and y) or more descriptive names (such as age, carname, totalvolume).

The operating environment of this tutorial: windows7 system, PHP version 7.1, DELL G3 computer

What do the variables in php mean?

Variables in php are "containers" used to store information.

Similar to algebra, PHP variables can be assigned a certain value (x=5) or an expression (z =x y).

Variables can have very short names (such as x and y) or more descriptive names (such as age, carname, totalvolume).

PHP variable rules:

Variables start with a $ symbol, followed by the name of the variable

The variable name must start with a letter or underscore character

Variable names can only contain letters, numbers and underscores (A-z, 0-9 and _)

Variable names cannot contain spaces

Variable names are case-sensitive ($y and $Y are two different variables)

lamp PHP statements and PHP variables are case-sensitive.

Create (declare) PHP variables

PHP has no command to declare variables.

A variable is created when you first assign a value to it:

Example

<?php
$txt="Hello world!";
$x=5;
$y=10.5;
?>

In the execution of the above statement, the variable txt will hold the value Hello world!, And the variable x will hold the value 5.

Note: When you assign a text value to a variable, please add quotation marks around the text value.

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