Pattern: a two-dimensional decorative repetition.
Andy Warhol sometimes took everyday objects and created art from them. In this case, it's rows of Campbell's soup cans, which create a pattern. From a distance, this pattern could almost be a type of plaid*, but the closer you get, the easier it is to see that it really is rows of soup cans.
Here are other examples of Patterns:
Pattern print & Quilt patterns (google images)
*Plaid: horizontal stripes and vertical stripes in different colors overlapping each other.