Choose your init system

The init system is the first program to start when a computer boots. Its role is to start other program automatically and to let you manage them more easily.

How to know which init system I have?

You can use this little script.

if [[ `systemctl` =~ -\.mount ]]; then echo "SystemD";
elif [[ -f /etc/init.d/cron && ! -h /etc/init.d/cron ]]; then echo using "SysVInit";
else echo "Can't tell"; fi

(Found here)