what are variables in php

Variables are containers for storing information

PHP variables

Just like algebra, PHP variables can be used to hold values ​​(x=5) and expressions ( z=x y).

Variable names can be short (such as x and y) or more descriptive (such as carname, total_volume).

PHP variable rules:

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

The variable name must start with a letter or an underscore

Variable name Cannot start with a number

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

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

Note: PHP variable names are case-sensitive!

The following example demonstrates how PHP creates variables

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

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