@thechildofroth@mastodon.world @jmaris@eupolicy.social @kde@floss.social systemd is a program responsible for managing a variety of system tasks on Linux systems, most notably managing the running and communication of background programs (such as the program which handles sound, the program which handles wifi, the program which controls printers, etc). But it also manages things like booting, networks, user sessions, DNS, etc. Systemd is relatively new and replaced a system where many different programs were responsible for all of the individual tasks, whereas Systemd is one monolithic whole. Some people preferred having many individual programs and thus dislike systemd. Some people also dislike that systemd is so ubiquitous it is almost mandatory (some programs won't work without it). But broadly these things are not really important to "normal" users.