Systemd

systemd Services: An Introduction

Nearly every modern Linux distribution uses systemd, which … pretty much manages the system. It has an enormous wealth of features, many of which we will describe, but we will begin with its service manager.

A systemd service is basically a unique application that can be controlled separately and has its own resources. That can include things that run in the background on the system, such as NFS drive shares, printing services, or DBUS. It can also include the things you actually want the system to do: Your web server, database server, and your own application server.