Of all the legitimate art movements that come to mind, I would say that the graffiti or street art movement most resembles the style of the Pop Art movement. Pop artists were all about mimicking the bold styles, colors and shapes used in commercial marketing to grab viewer’s attention and make statements about the nature of art and its relationship with socitey. Many graffiti artists use similar, bold, striking shapes paired with text to capture the viewer’s attention and communicate their message. Many also try to communicate scathing social commentary, such as Shepard Fairey’s "Obey" street art pieces that are portrayed in the film Exit Through the Gift Shop. These pieces make us think of the power of advertizing and how ad executives gather to figure out how to create marketing campaigns that will make us obey, and buy a product.
Another genre of art that resembles graffiti work in terms of concept, is Installation Art. The eNotes/Wikipedia page on Installation Art defines it as “an artistic genre of site-specific, three-dimensional works designed to transform a viewer's perception of a space.” This is precisely what the 21st century street artists are trying to do. It could be considered the truest form of Installation Art because they are not just trying to fill a contrived, 'fake' gallery space; they are altering the spaces of everyday life.