You're walking past a brick wall in Brooklyn when you spot it: a stenciled rat holding a paintbrush. Is it vandalism or art? Twenty years ago, the answer seemed obvious. Today, that same image might sell for millions at Sotheby's.

From Subway Cars to Sotheby's

Modern graffiti exploded onto New York City subway cars in the late 1960s. Young artists called themselves "writers" and tagged their names across trains and buildings. They weren't trying to make pretty pictures. They wanted to leave their mark on a rapidly changing urban landscape where they felt invisible.

By the 1970s, graffiti had become a cornerstone of hip-hop culture, standing alongside breakdancing, DJing, and rapping. But city officials saw only vandalism. New York launched aggressive cleanup campaigns. Police arrested taggers. Property owners scrubbed walls clean overnight.

The art world, however, started paying attention. Galleries in downtown Manhattan began noticing something raw and urgent in these spray-painted letters. The question shifted from "Is this legal?" to "Is this art?"

The Pioneers Who Changed Everything

Jean-Michel Basquiat started as SAMO, tagging cryptic messages across SoHo and the East Village with collaborator Al Diaz. His phrases mixed poetry with social commentary. Within a few years, he'd moved from sidewalks to canvas, collaborating with Andy Warhol and showing in prestigious galleries.

Basquiat's trajectory proved street artists could transition to the mainstream without losing their edge. When he died at 27 in 1988, he'd already become one of the most important artists of the 20th century. He even appeared as a DJ in Blondie's "Rapture" music video, a moment that placed street art alongside classical ballet in pop culture.

Keith Haring took a different approach. He created chalk drawings on unused advertising panels in subway stations during the 1980s. Anyone riding the train could see his work for free. His simple figures and bold lines addressed AIDS awareness, apartheid, and LGBTQ+ rights.

Haring pioneered something radical: making street art affordable. He sold pencil cases and sketchbooks featuring his designs. Critics called it selling out. Haring called it democratizing art. Why should only wealthy collectors own original work?

The Banksy Effect

No one has done more to legitimize street art than an artist whose identity remains unknown. Banksy emerged from Bristol, England, in the early 1990s. His first large-scale mural appeared there in 1999.

Banksy developed a mostly monochromatic stencil technique. He adopted it partly for speed—stencils let you work fast before police arrive—and partly as homage to French artist Blek le Rat, who pioneered the method in 1980s Paris.

His work combines dark humor with political commentary. A girl releases a heart-shaped balloon. Rats carry protest signs. Riot police grow flower bouquets from their visors. The images look simple but carry complex messages about capitalism, war, and surveillance.

In 2018, Banksy pulled his most famous stunt. Seconds after his painting sold at auction, it began shredding itself through a hidden mechanism in the frame. The art world gasped. Ironically, the half-destroyed work later sold for an even higher price. Banksy had simultaneously mocked and validated the commercial art market.

Beyond the Boys' Club

For decades, graffiti remained overwhelmingly male. Lady Pink broke through in the 1970s as one of the first women in the scene. Her fantastical murals brought spirituality and femininity to a movement dominated by aggressive lettering and territorial marking.

Shepard Fairey created the Obey campaign and later designed the iconic Obama Hope poster. His colorful graphics with bold phrases get screenprinted and wheatpasted on walls worldwide. He proved street art could influence mainstream political discourse.

Brazilian twins Gustavo and Otavio Pandolfo, known as OSGEMEOS, brought Latin American perspectives to global street art. Their yellow-skinned characters and dreamlike scenes draw from Brazilian folklore. The Hirshhorn Museum presented their first US survey, displaying roughly 1,000 artworks and photographs.

The Museum Paradox

Here's the contradiction: street art thrives on illegality, yet museums now compete to exhibit it. The Smithsonian's Hirshhorn Museum hosted a Basquiat × Banksy exhibition from September 2024 through September 2026. It marked the first time either artist's work appeared in this prestigious institution.

Museums aren't just showcasing aesthetics. They're preserving historical records of urban life and marginalized voices. Street art documents neighborhoods before gentrification erases them. It captures political movements in real time. It shows what mattered to communities that traditional art institutions ignored.

But something gets lost in translation. A Banksy stencil hits differently on a crumbling warehouse wall than under gallery spotlights. The context matters. Street art gains power from its location, its impermanence, its illegality. Removing it from the street removes part of its meaning.

Graffiti Versus Street Art

These terms aren't interchangeable. Graffiti focuses on stylized lettering, symbols, and tags. It emphasizes the artist's identity or crew affiliation. The aesthetic matters, but so does the act of marking territory.

Street art encompasses broader visual expressions: murals, stencils, wheatpaste posters, installations. It often aims to engage the public on social or political themes. Sometimes property owners give consent. Street art tends to be more accessible to general audiences than graffiti's insider codes.

Dondi White revolutionized graffiti with intricate lettering that emphasized precision and bold color schemes. Futura 2000 took graffiti abstract, collaborating with Nike, Supreme, and The Clash. Both pushed graffiti's boundaries while respecting its roots.

The Commodification Question

Cities that once arrested street artists now commission them for large-scale murals. Urban tourism thrives on Instagram-worthy walls. Festivals celebrate what used to be crimes. Brands hire street artists for advertising campaigns.

Some artists embrace this shift. Others resist. Traditional graffiti continues as a subcultural movement that rejects commercialization. Writers still risk arrest to tag trains. They see gallery shows and brand deals as betrayals of graffiti's rebellious spirit.

The tension is real. Can street art maintain its edge after entering museums? Does legitimacy require compromise? Or has the movement simply evolved, creating space for both underground taggers and celebrated muralists?

What Happens Next

Harvard Graduate School of Design now offers courses on curating public art. Experts like Pedro Alonzo teach the evolution of urban art in academic settings. Street art has become a serious field of study.

Documentary films preserve the movement's history. "Downtown 81" captured Basquiat's early days. Banksy's "Exit through the Gift Shop" questioned authenticity in the street art market. These films ensure future generations understand how radically perceptions have shifted.

Today's street artists navigate complex terrain. They can pursue gallery representation, brand partnerships, and museum exhibitions. Or they can stay underground, creating work that disappears when authorities paint over it. Many do both.

The rat with the paintbrush you spotted in Brooklyn? It's still vandalism by legal definition. But it's also art that makes you think about who owns public space and whose voices get heard. That's the evolution: not from vandalism to art, but toward recognizing it was always both.