What is Art?

[Raisa]

There is no universally accepted definition of art. Although commonly used to describe something of beauty, or a skill which produces an aesthetic result, there is no clear line in principle between (say) a unique piece of handmade sculpture, and a mass-produced but visually attractive item. We might say that art requires thought - some kind of creative impulse - but this raises more questions: for example, how much thought is required? If someone flings paint at a canvas, hoping by this action to create a work of art, does the result automatically constitute art?

Even the notion of 'beauty' raises obvious questions. If I think my kid sister's unmade bed constitutes something 'beautiful', or aesthetically pleasing, does that make it art? If not, does its status change if a million people happen to agree with me, but my kid sister thinks it is just a pile of clothes?
Art: Multiplicity of Forms, Types and Genres

Before trying to define art, the first thing to be aware of, is its huge scope.

Art is a global activity which encompasses a host of disciplines, as evidenced by the range of words and phrases which have been invented to describe its various forms. Examples of such phraseology include: "Fine Arts", "Liberal Arts", "Visual Arts", "Decorative Arts", "Applied Arts", "Design", "Crafts", "Performing Arts", and so on.

Drilling down, many specific categories are classified according to the materials used, such as: drawing, painting, sculpture (inc. ceramic sculpture), "glass art", "metal art", "illuminated gospel manuscripts", "aerosol art", "fine art photography", "animation", and so on. Sub-categories include: painting in oils, watercolours, acrylics; sculpture in bronze, stone, wood, porcelain; to name but a tiny few. Other sub-branches include different genre categories, like: narrative, portrait, genre-works, landscape, still life.

In addition, entirely new forms of art have emerged during the 20th century, such as: assemblage, conceptualism, collage, earthworks, installation, graffiti, and video, as well as the broad conceptualist movement which challenges the essential value of an objective "work of art".
source http://www.visual-arts-cork.com/art-definition.htm