you should get into the habit of "cleaning" any $_GET, $_REQUEST, and $_POST data .... the above is a vb function that cleans/converts data that will be used
if you study the vb files or any product/plugin found here (vb.org) you will find the above line more frequently
The ?: operator is used as a shorthand replacement for the if-then-else conditional statement; the general form is condition ? op1 : op2. If condition is true, the statement evaluates as op1; otherwise, it evaluates as op2.