<?php
$id=$_GET['id'];
if($id==1)
   echo "Welcome Guest, please register to use this page.";
else
   echo "Welcome back!";
?>

This is fairly simple to understand, and most people have statements like this through out any webpage. There is a trick that makes the coding much shorter. I have no idea what it is called, so we will call it an inline-if-statement. It utilizes the question mark (?) and colon (:) to execute simple if statements. Lets rewrite the above code:

<?php
$id=$_GET['id'];
echo "Welcome ".($id==1?"Guest, please register to use this page.":"back!");
?>

We summed up those 4 lines into one line of code. I typically encase the statement in parenthesis, but you don’t need to. The first part is the if-statement. If($id==1) becomes $id==1?. Then if $id was equal to 1, it would append "Guest, please register to use this page." to "Welcome ". else is now just a colon : and separates the two values.

Why is this useful? Well its quicker code. 4 lines of code is now compressed to a single line.

Why would you not use it? Well if you need to do other things within the if-statement. This is strictly for displaying data. If you need to change variable values, or call a function, then you would definitely not use this. You would also not use this if you have “else if” statements. This is strictly, if-else.

Hope this helps!