Proficiencies (DMG)

A character in the AD&D game, like anyone else, has a variety of skills and talents. He is good at some things (because they are used in his profession or hobby) and poor at those he has studied casually or not at all. These skills and talents are called proficiencies.
Proficiencies aren't exactly like the skills people pick up in school or in the "real" world. They tend to be unrealistically broad or narrow, depending on the subject. The fishing proficiency, for example, assumes the character knows everything about both rod-and-reel fishing and net fishing. In reality, these are two vastly different skills.
At the other end of the spectrum, weapon proficiencies tend to be very precise, highlighting the subtle differences between weapons. A long bow and a short bow differ in size, weight, pull, arrow length, and balance. Each demands different practices to get optimum utility.
When using proficiencies, remember that these rules are not intended to recreate reality. It might have been more realistic to list different proficiencies for each aspect of medieval botany—horticulture, herbalism, mycology, etc. But in the context of a game, these are much better grouped under a single proficiency. Individually, each proficiency would be of such limited usefulness that all of them would become worthless. Other proficiencies, particularly weapons, go to the other extreme.
* Weapon Proficiencies
* Min/Maxing
* NPC Proficiencies
* Nonweapon Proficiencies
* Adding New Proficiencies