What is += used for?

Question

I think this is a dumb question but I could not find it on php. Why is a + with the = in the following code:

function calculateRanking()
{
    $created = $th         


        

Answer 1

x += 10 is simply a shorter way to write x = x + 10.

In this case, the code is finding the time difference in hours from a time difference structure.