With SystemV, we talked about runlevels.
With systemd, we talk about targets.

Relationship between runlevels and targets:

Runlevel		Target				Description
0	runlevel0.target, poweroff.target	Power off
1	runlevel1.target, rescue.target		Non-graphical single-user
2,3,4	runlevel[234].target, multi-user.target	Non-graphical multi-user
5 	runlevel5.target, graphical.target	Graphical multi-user
6 	runlevel6.target, reboot.target		Reboot


Check the system’s current default target:

 # systemctl get-default

Set the default target:

 # systemctl set-default multi-user.target

If you wish to switch immediately to rescue.target:

 # systemctl isolate rescue