The Weapon enumerator contains tables used to identify the capabilities and types of a particular weapon. Additionally the Weapon.flag table is large table that defines every category of weapon.
Weapon.flag information is available in its own article.
The Weapon.flag enumerators are commonly used to define the weapons the AI are allowed to use for a given task. Alternatively information like category or guidance type can be used as generalized criteria for assorted scripts. For example instead of making a table of every single laser guided missile you can simply check its guidance type.