difference between $a==5 and 5==$a in php

Question

Today I have faced a question, I was unable to answer it, I have tried by making a php program but was unable to find out the exact reason for it if $a=5 then both($a==5 and 5==$a) are giving me output as boolean true and, if $a != 5 then both ($a==5 and 5==$a ) are giving me output as boolean false Can anyone tell me what is the difference between $a==5 and 5==$a from any language point of view.

**Program**
$a = 3;
var_dump( 5==$a );
var_dump( $a==5 );
$a = 5;
var_dump( 5==$a );
var_dump( $a==5 );


**Output**
boolean false

boolean false

boolean true

boolean true

Answer 1

Comparisons like that are not affected by which value you write first. However, it is best practice to put the literal first, e.g. 5 == $x because if you mess up and only enter one equals sign, you'll get an error instead of an accidental value assignment, which is far easier to debug.