Part artistic movement and part subcultural phenomenon, Street Art is controversial and undefined in its origins, which range from gang symbology to government-approved murals to elaborate illegal installations. Some of the earliest recorded evidence of street art is among various counter-culture groups of the 1920s and 1930s in New York City. Gangs used markings on trains, walls and signs to mark territory. At the same time, Mexican artists like Diego Rivera, José Clemente Orozco and David Alfaro Siqueiros were creating elaborate, full color murals promoting the ideals of the Mexican Revolution.

While many considered this type of art a public scourge, the anti-establishment era of the 1960s saw a boom in highly political young street artists who elevated common graffiti from criminal scribblings to multi-faceted works of public art. As the roots of hip hop culture took hold in the 1970s, the bubble letters and simple tags of anonymous artists like TAKI 183 and Phase2 were seen around New York. It was in the 1980s that the worlds of fine art and street art converged, when celebrated motifs such as Keith Haring’s outlined characters and Jean-Michel Basquiat’s SAMO graffiti appeared on train cars, murals and city walls. The feminist collective Guerrilla Girls used flashy posters and billboards to call out sexism in the art world, such as their 1989 piece, "Do women have to be naked to get into the Met Museum?" As artists and activists began to move more seamlessly between the private gallery world and public tagging, a new generation of street artists came about, expanding both practical and ideological limitations of creative “vandalism.”

Integrating wheat pasting, stickers, stencils, sculptures, yarn bombing, mosaic tiling, and LED lights in their work, contemporary street artists defy conventional categorization. Important figures include Barbara Kruger, Jenny Holzer, Kenny Scharf, Swoon, ROA, JR, Blu, and Barry McGee, all of whom developed a unique visual language. On a global level, influential British stencil artist Banksy and American graphic artist Shepard Fairey have become celebrated in both fine art and pop culture for their characteristic street art styles.