A long time ago, the melee combat skills were simplified into a single skill - Melee. This was never reflected in the actual rules, and the related techniques have not been included in the Characters article because it was focused on modern day combat.
This has now been rectified, and the main set of melee techniques for use in low tech (fantasy/historical) campaigns is now included in the core rules. They may require a little bit of tweaking, but at least they're visible.
There are also a number of techniques for unarmed combat which need to be added. They will probably go into a separate martial arts article, together with other melee fighting styles such as fencing and Kenjutsu, rather than being slotted into the core rules. This is simply because there are a lot of them, and it simplifies things to keep them separate.