systemd is a suite of basic building blocks for a Linux system. It provides a system and service manager that runs as PID 1 and starts the rest of the system.
systemd provides aggressive parallelization capabilities, uses socket and D-Bus activation for starting services, offers on-demand starting of daemons, keeps track of processes using Linux control groups, maintains mount and automount points, and implements an elaborate transactional dependency-based service control logic. systemd supports SysV and LSB init scripts and works as a replacement for sysvinit.
Other parts include a logging daemon, utilities to control basic system configuration like the hostname, date, locale, maintain a list of logged-in users and running containers and virtual machines, system accounts, runtime directories and settings, and daemons to manage simple network configuration, network time synchronization, log forwarding, and name resolution.
Welcome to Fedora 20 (Heisenbug)! [ OK ] Reached target Remote File Systems. [ OK ] Listening on Delayed Shutdown Socket. [ OK ] Listening on /dev/initctl Compatibility Named Pipe. [ OK ] Reached target Paths. [ OK ] Reached target Encrypted Volumes. [ OK ] Listening on Journal Socket. Mounting Huge Pages File System... Mounting POSIX Message Queue File System... Mounting Debug File System... Starting Journal Service... [ OK ] Started Journal Service. Mounting Configuration File System... Mounting FUSE Control File System... [ OK ] Created slice Root Slice. [ OK ] Created slice User and Session Slice. [ OK ] Created slice System Slice. [ OK ] Reached target Slices. [ OK ] Reached target Swap. Mounting Temporary Directory... [ OK ] Reached target Local File Systems (Pre). Starting Load Random Seed... Starting Load/Save Random Seed... [ OK ] Mounted Huge Pages File System. [ OK ] Mounted POSIX Message Queue File System. [ OK ] Mounted Debug File System. [ OK ] Mounted Configuration File System. [ OK ] Mounted FUSE Control File System. [ OK ] Mounted Temporary Directory. [ OK ] Started Load Random Seed. [ OK ] Started Load/Save Random Seed. [ OK ] Reached target Local File Systems. Starting Recreate Volatile Files and Directories... Starting Trigger Flushing of Journal to Persistent Storage... [ OK ] Started Recreate Volatile Files and Directories. Starting Record System Reboot/Shutdown in UTMP... [ OK ] Started Trigger Flushing of Journal to Persistent Storage. [ OK ] Started Record System Reboot/Shutdown in UTMP. [ OK ] Reached target System Initialization. [ OK ] Reached target Timers. [ OK ] Listening on D-Bus System Message Bus Socket. [ OK ] Reached target Sockets. [ OK ] Reached target Basic System. Starting Permit User Sessions... Starting D-Bus System Message Bus... [ OK ] Started D-Bus System Message Bus. Starting Login Service... Starting Cleanup of Temporary Directories... [ OK ] Started Permit User Sessions. [ OK ] Started Cleanup of Temporary Directories. Starting Console Getty... [ OK ] Started Console Getty. [ OK ] Reached target Login Prompts. [ OK ] Started Login Service. [ OK ] Reached target Multi-User System. Fedora release 20 (Heisenbug) Kernel 3.9.2-200.fc18.x86_64 on an x86_64 (console) fedora login: