The great mass of humanity, elf-kind, the dwarven clans, and halflings, are "0-level" (zero-level) characters. They can gain in wisdom and skill, but they do not earn experience points for their activities. These common folk form the backbone of every fantasy world, doing the labor, making goods, selling cargos, sailing oceans, building ships, cutting trees, hauling lumber, tending horses, raising crops and more. Many are quite talented in the various arts and crafts. Some are even more proficient than player characters with the same training. After all, 0-level characters earn their livings doing this kind of work. For player characters such proficiencies are almost more of a hobby.
For the vast majority of 0-level NPCs you create and use in your game, all you need to know is a name, a personality, and an occupation. When the characters deal with the blacksmith or the innkeeper, there's no need to create ability scores, THACO, to-hit adjustments, Armor Class, and the like. This does assume, of course, that your player characters don't go attacking every blacksmith and innkeeper in sight. If they do, you need to know a little more about 0-level characters.
Ability Scores: These range from 3-18. For simplicity, don't worry about racial modifiers for the demihuman races. Racial modifiers to combat, Armor Class, hit points, etc., do apply.
Proficiencies: At best, a 0-level character will have one weapon proficiency, if that character's profession reasonably allows for it. For example, a blacksmith could be proficient with a warhammer and an innkeeper might be allowed skill with a club (the axe handle under the bar...), but there's little chance a clerk is going to be skilled with any type of weapon.
In nonweapon proficiencies, 0-level characters have as many as are needed (and reasonable) given their profession and age. Thus, a blacksmith might be quite accomplished at the forge, having spent several proficiencies on the slot. Novices and incompetent craftsmen have the bare minimum training and skill. Typical journeymen spend two or three slots on their main skill. Experts and brilliant artists usually devote all their ability to a single proficiency. Masters, who watch over the work of journeymen and apprentices, are normally no more accomplished than journeymen but have additional proficiencies in other business areas.
Hit Points: The majority of people have from 1-6 hit points. Dwarves and gnomes average from 1-8 hit points. Adjustments can be made for occupation or condition as indicated on Table 10, below.
0-Level Hit Points by Title
Some players think it is unrealistic that a typical peasant can be killed by a single sword blow, a fall from a horse, or a thrown rock. In the real world, people can and do die from these causes. At the same time, however, others survive incredible injuries and wounds.
When it is necessary to the success of an adventure (and only on extremely rare occasions), you can give 0-level characters more hit points. The situation could have come about for any number of reasons: magic, blessings from on high, some particularly twisted curse (the peasant who could not die!)you name it.
It is also useful to make important NPCs, such as 0-level kings or princes, tougher than the average person. This is particularly important in the case of rulers, otherwise some crazed player character is going to overthrow the campaign kingdom with a single swipe of his sword. This is normally not a desirable result.