is a modern replacement for rc scripts/etc/rc.d/*   /etc/rc* and the interpreting shells, designed for startup performance and faster boot times.  System startup tasks are described in an ASCII config file that is converted to binary anytime before booting.  During boot, reads the binary file and multiple threads run tasks in parallel as directed.  See the links below for more info.

4-Cores/8-Threads or more, including embedded systems, servers, and HEDTs

Linux and other UNIX flavors, often those with init(8) or similar