Here is a quick little snippet which can prove to be quite useful.

This snippet will check to see if a number is odd or even.

In Javascript

function checkEven(val){
     return (val%2 == 0);
}

val = 3;

if(checkEven(val)){
    alert("Number is even");
} else {
    alert("Number is odd");
]

In PHP

In PHP it's actually exactly the same just fix the variables.

function checkEven($val){
     return ($val%2 == 0);
}

$val = 3;

if(checkEven($val)){
    echo "Number is even";
} else {
    echo "Number is odd";
]