In addition to existing martial classes, you may also choose to become a Disciple of the Hand—one who synthesizes new items from materials on hand—or a Disciple of the Land—one who harvests Eorzea's natural resources from the field.
Becoming proficient in one of these disciplines will help you acquire or create new items to aid you on your journeys.
Disciplines of the Hand
Disciples of the Hand deal in the creation of all manner of items, from battle gear and medicine to food and furnishings.
There are a total of eight disciplines you may choose from, and each specializes in a different product. Blacksmiths, for example, are skilled in metalwork, while culinarians can create delicious cuisine.