<html><body>$txt1 = "Hello";$txt2 = " world!";echo $txt1 . $txt2; </body><!-- Mirrored from www.w3schools.com/php/phptryit.asp?filename=tryphp_oper_string1 by HTTrack Website Copier/3.x [XR&CO'2014], Mon, 27 Jan 2020 02:29:31 GMT --></html>