The systemd software suite provides fundamental building blocks for a Linux operating system. It includes the systemd “System and Service Manager”, an init system used to bootstrap user space and manage user processes.

systemd aims to unify service configuration and behavior across Linux distributions.^[8] It replaces the UNIX System V and BSD init systems. Since 2015, the majority of Linux distributions have adopted systemd, and it is considered a de facto standard.^[1]

The name systemd adheres to the Unix convention of naming daemons by appending the letter d. It also plays on the term “System D“, which refers to a person’s ability to adapt quickly and improvise to solve problems.

SysV->upstart->systemd

Source: systemd – Wikipedia