Your skills can be seen through the '@' command and they reflect your proficiency with various weapons.
There are the following skills in the game:
- Unarmed Combat
- Small swords
- Large swords
- Blunt Weapons
- Uncategorized Weapons
- Right Accustomization - This skill (and likewise the Left Accustomization skill) is trained when you wield and use one item for a prolonged period of time. Be aware that switching to another item will reset this skill to zero and you have to build it up again.
- Left Accustomization
Skills are automatically trained while fighting and give you a bonus to your combat abilities with the given weapon type. Some non-weapon items use one of the weapon skills (e.g. fighting with banana peels will train Whips skill, sticks train Blunt Weapons), while the rest will train Uncategorized Weapons. Also, your skills can rust if you evade fighting for too long, but the loss is completely negligible.
For a deeper insight into the in-game implementation, see here and beware of spoilers.