One of the most helping definition or explanation comes from Seth Godin:
I define art as having nothing at all to do with painting.
Art is a human act, a generous contribution, something that might not work, and it is intended to change the recipient for the better, often causing a connection to happen.
Five elements that are difficult to find and worth seeking out. Human, generous, risky, change and connection.
You can be perfect or you can make art.
You can keep track of what you get in return, or you can make art.
You can enjoy the status quo, or you can make art.
The most difficult part might be in choosing whether you want to make art at all, and committing to what it requires of you.
– Seth Godin