UNIT                     LOAD   ACTIVE SUB     DESCRIPTION
accounts-daemon.service  loaded active running Accounts Service
acpid.service            loaded active running ACPI event daemon
apache2.service          loaded active running LSB: Apache2 web server
avahi-daemon.service     loaded active running Avahi mDNS/DNS-SD Stack
bind9.service            loaded active running BIND Domain Name Server
colord.service           loaded active running Manage, Install and Generate Color Profiles
cron.service             loaded active running Regular background program processing daemon
cups.service             loaded active running CUPS Scheduler
dbus.service             loaded active running D-Bus System Message Bus
getty@tty1.service       loaded active running Getty on tty1
irqbalance.service       loaded active running LSB: daemon to balance interrupts for SMP systems
isc-dhcp-server.service  loaded active running ISC DHCP IPv4 server
lightdm.service          loaded active running Light Display Manager
lvm2-lvmetad.service     loaded active running LVM2 metadata daemon
ModemManager.service     loaded active running Modem Manager
NetworkManager.service   loaded active running Network Manager
nfs-idmapd.service       loaded active running NFSv4 ID-name mapping service
nfs-mountd.service       loaded active running NFS Mount Daemon
ntp.service              loaded active running LSB: Start NTP daemon
polkitd.service          loaded active running Authenticate and Authorize Users to Run Privileged Tasks
rpc-gssd.service         loaded active running RPC security service for NFS client and server
rpc-statd.service        loaded active running NFS status monitor for NFSv2/3 locking.
rpc-svcgssd.service      loaded active running RPC security service for NFS server
rpcbind.service          loaded active running RPC bind portmap service
rsyslog.service          loaded active running System Logging Service
rtkit-daemon.service     loaded active running RealtimeKit Scheduling Policy Service
snapd.service            loaded active running Snappy daemon
ssh.service              loaded active running OpenBSD Secure Shell server
systemd-journald.service loaded active running Journal Service
systemd-logind.service   loaded active running Login Service
systemd-udevd.service    loaded active running udev Kernel Device Manager
upower.service           loaded active running Daemon for power management
user@10000.service       loaded active running User Manager for UID 10000
user@108.service         loaded active running User Manager for UID 108
whoopsie.service         loaded active running crash report submission daemon

LOAD   = Reflects whether the unit definition was properly loaded.
ACTIVE = The high-level unit activation state, i.e. generalization of SUB.
SUB    = The low-level unit activation state, values depend on unit type.

35 loaded units listed. Pass --all to see loaded but inactive units, too.
To show all installed unit files use 'systemctl list-unit-files'.