Major Categories of Art
Still Life - Is the presentation of inanimate objects. One of the purposes for this art category is to celebrate materialistic things. Another is the practice in the study of perception itself, texture, shape, etc.
Landscape - Is one of the oldest subjects for art and was used as a communication of an existing or non-existing environment; and to commemorate a particular place (near or far). Types of landscapes include person generated, fanciful, illusionistic, impressionistic, cityscapes, seascapes, street scenes, village scenes, etc.
Portraiture - Is a major subject for art, and its reason quite obvious - people want to be remembered/to have their existence commemorated. Aristocracy were usually the subjects chosen to be commemorated and were usually done so in a fashion where they were generalized beyond reality to eliminate specifics (flaws). Although to contrast, many were individualized picking up all minute characteristics.
Self-Portrait - One reason for this category was perhaps lack of models and for the practice in the study of portraiture. Another reason, to capture something beyond mere resemblance, such as character, personality, and emotion. In otherwords, to present a surface of the self to convey a deeper meaning.
Religious - Another major art category where images were created for the purpose of perpetuating religious belief. Generally religious art is loaded with attributes (symbols that help you recognize certain things/who a particular person is). A couple examples: St. John the Baptist is generally recognized by his camel hair coat; St. John the Evangelist often depicted with a bird or a book; and St. John the Apostle is always presented on the right side of Christ.
History - History art was created to commemorate events in history and to teach morals, i.e., "the right image to remember".
Allegory - Presentation of a visual metaphor. Communication on a more general level/figurative. Not a lot of information given, but more the interrelationship of images/subject to present a complex idea.
Dutch Genre Painting - The depiction of everyday life scenes of common people and peasants.
Nude - Very few male nudes were created unless depicting a biblical scene. Often female nudes were presented in a very object oriented manner.
Imaginary/Fantastic Imagry - The rendering of dreamstates.