Smack is a Linux kernel security module that protects data and process interaction from malicious manipulation using a set of custom mandatory access control (MAC) rules, with simplicity as its main design goal. It has been officially merged since the Linux 2.6.25 release, it was the main access control mechanism for the MeeGo mobile Operating System. It is also used to sandbox HTML5 web applications in the Tizen architecture, in the commercial Wind River Linux solutions for embedded device development, in Philips Digital TV products., and in Intel's Ostro OS for IoT devices.