Here is a good command that will give you a list of services and whether or not they have started.
From your terminal window / command prompt run:
systemctl list-unit-files --type=service
and it will give you a list of various services that are enabled / disabled etc.
username@computername:~$ systemctl list-unit-files --type=service UNIT FILE STATE accounts-daemon.service enabled acpid.service disabled alsa-restore.service static alsa-state.service static alsa-utils.service masked anacron.service enabled apparmor.service enabled apport-autoreport.service static apport-forward@.service static apport.service generated apt-daily-upgrade.service static apt-daily.service static autovt@.service enabled avahi-daemon.service enabled blk-availability.service enabled bluetooth.service disabled bolt.service static
If that is too much and you just want to see a list of running services (for example) then run the command:
systemctl list-unit-files --type=service | grep enabled
this will filter out all services except those enabled.