Fallout 3's V.A.T.S. system is back in Fallout 4. Lots of people loathed it but there are plenty of other people that loved to slow down time during combat and pick their spots when fighting one enemy or a group of formidable foes. We fall into the latter.
For those unfamiliar with V.A.T.S., it allows you to essentially stop time and focus points in on specific parts of a creature or human. Damange depends on the distance, weapon and the type of opponent you're facing in combat.
Of course, you're also able to fight enemies in real-time, just like Skyrim, though V.A.T.S. will almost certainly be necessary in some fights. Bethesda showed off a battle between the Vault Dweller in Power Armor and a Deathclaw and V.A.T.S. looked like it was critical to the fight.