Intellectual property is a generic term describing products of the human intellect that have economic value. It includes works of authorship such as writings, films and music, inventions and information or know-how not generally known.
Intellectual property is considered property because the law gives the owners of such works legal rights similar to the rights of owners of real estate or tangible personal property such as automobiles. Intellectual property may be owned and bought and sold the same as other personal property.
Despite these similarities, there are some significant ways in which owning intellectual property is quite different from owning a house or car. For example, if you pay an IC to build a house, you own the house. But you can pay an IC to create intellectual property and yet not own the finished product.