What does the PHP syntax $var1->$var2 mean?

Question

What is the explanation for the following syntax?

$var1->$var2 // Note the second $

Answer 1

You are calling a property on $var1 that is named the same as the value of $var2.

For example:

$var2 = "name";

// The following are equivalent
$var1->name;
$var1->$var2;