Art, in my personal opinion, is anything that is created by someone. That definition may seem broad, but there are so many types of art. A painting is a work of art created by an artist. Architecture is art created by an architect. A novel is a work of art created by an author. This earth could be considered art created by God. Generally, art is created for a purpose, such as to provide office space, to make a statement, or for pure enjoyment. I think that all art is intentional, whether it "has" to be or not in order to be considered art. No one just creates something or paints something for no reason. Most works of art have a purpose, but someone could create something like a painting because it helps them to calm down and relax. Even then, it would still be considered intentional.
For art to be considered "art," I do not believe that it has to be representational, but art is representational just like it is intentional. Artists may not consciously make a work of art representational, but all works of art represent something such as the artist's emotions and interests. An example would be the "Hall of the Bulls." It was created to possibly tell a story or to decorate, but it represents the hunter's interest in the animals they hunted.
Art is whatever the artist makes it. Art is not just paintings or sculptures. It is anything that is created. All art is created for some kind of purpose and whether or not the artist wanted it to, art represents something. I do not think that it has to represent something or be intentional in order to be considered art. Art is such a broad category with definitions that people constantly change. It is something that is inspired by events, people, or emotions. It should be fun and exciting as well as soothing. That is what I think art is.