The main things to remember are the following.
- Choose your Maneuver (p. B363-368): Aim, All-Out Attack, All-Out Defense, Attack, Change Posture, Concentrate, Do Nothing, Evaluate, Feint, Move, Move and Attack, Ready, or Wait.
- Turns are abstract but are basically a second long.
- Roll lower than or equal to your modified skill on 3d6 to hit
- Defender rolls 3d6 for equal to or lower against a Block, Dodge or Parry score to avoid the attack.
- If Defender fails the attacker rolls damage. Here is one of the few places a higher roll is better than a low roll. Subtract the targets DR from the damage and apply any wounding modifiers on damage that penetrates.
- Defender may need to make some rolls to stay conscious or alive if damage was severe enough.
That is pretty much the basic combat system in a nut shell.
Keeping track of maneuver choices is one of the hardest things to get used to as most other games do not give you this much flexibility. Use Combat Cards to help.
Now it can be that simple or much more detailed depending on the group.
In GURPS you can target specific Hit Locations (p. B398) for special damage or other effects at various skill penalties. Also Martial arts and other abilities can give you special options in combat and some of those can be complicated. However you never have to use them and can stick to basic combat if you prefer. GURPS is all about choices.
Relevant free items
Certain Blogs have some great examples of Combat and explanations
Shooting Dice A popular author for modern warfare and guns he has some nice writeups of movie action scenes.
Gaming Ballistic The author of this blog wrote GURPS Technical Grappling and put up several worked examples of unarmed combat. In fact Technical Natasha is a great write up of a Black Widow fight. Here is a nice page on Ranged combat
- GURPS Combat Material Another page of references.
Some specific web pages related to Combat.Just Roll 3d6 Combat Tag includes several posts on combat that are useful reading,
Aerial Combat by Mlangsdorf
The Mook Combat Examples (Several types, links on the left of that page).
Shooting Dice: Guns and Gaming Plays out several combats from books and movies. A bit hard to find them but if you like guns the entire site is worth reading. For Example here is a John Wick fight