Street art today holds just a slight, precarious connection to the illegal graffiti scene it once grew out of. While both are statements in public spaces, graffiti focuses on the written whereas street art, the visual. As a result, street art can now be found in galleries and museums, which has led to strife in the scene: How believable and trustworthy is street art's street credentials?

One of Mexico's most famous painters, Diego Riviera, is also an important figure of Mexican muralism, the art of painting murals on walls in public spaces. Contracted by the Mexican government, the murals often contain nationalistic messages and can still be found on nearly every public building in Mexico. Many protest-oriented graffiti artists have distanced themselves from Muralismo.

Illegal wall painting began in São Paulo, Brazil, during the military dictatorship from 1964-1985. Pixação developed as a protest movement as it sprayed tall buildings with tags and slogans written in a cryptic fashion. Adventurous climbing was on the agenda, as one of the challenges was to reach the tops of tall buildings. Latin America's street art scene was definitely influenced by Pixação.

Graffiti could be found on the streets of Paris long before it made its way to New York, as the Romanian photographer Brassaï documented in the 1930s. He published a picture book in 1960 under the title, "Graffiti," which included an essay on the subject by Pablo Picasso. Shown here is an image from the photographer's exhibition at Centre Pompidou in 2016.

New York was the city that made graffiti art popular - and brought street art into the mainstream. Decisive to the art's broader acceptance was the 1984 picture book "Subway Art," which showed the artistic tags thrown up on the sides of subway cars. That same year, the film "Wild Style" connected the art form with hip hop culture.

In New York in the 1970s, colorful writings on the wall were part of the city landscape. Relatively early on, they were accepted by the art world at large and artists like Keith Haring began to employ the techniques used in the graffiti scene. He started his series of "Subway Drawings" in December 1980 and carried on with them through 1985.

Jean-Michel Basquiat won over the New York gallery scene in the 1980s. Frequently said to be aligned with the graffiti scene, he disagreed. "I am not a part of graffiti art." Yet he employed their technique: His tag, SAMO, has been sprayed on walls across New York as a form of anti-graffiti. Even through today, his labeling in art history books is controversial.

Harald Naegeli became famous at the end of the 1970s as the "Sprayer from Zurich." After being discovered in 1981 and prosecuted, Naegeli fled to Germany. He was extradited to Switzerland in 1984, where he served a six-month sentence. Still, with his politically motivated street art, he belongs to the group of founding fathers of street art in Europe.

In the 1980s, the Berlin Wall was discovered to be the perfect canvas for graffiti. Scribbles on the wall were transformed into artistic graffiti; the northern portion especially became a playground for American-style graffiti. After Germany's reunification, 118 international artists were contracted to decorate the remains of the wall on Berlin's Mühlenstraße.

Central to Argentina's street art scene, stencil art grew as spraying served as a form of protest against the military junta that led the country from 1976-1983. Stencils came in handy as the art had to be done quite quickly to avoid arrest. Following the 2001 economic crisis, street art boomed anew, especially in Buenos Aires. Much of the colorful street art there was created by invited artists.

London is a city that is under constant surveillance. That's had an influence on the graffiti scene as tags and written graffiti is often thrown up "quick and dirty" - aggressive in style. After Banksy's work gained wider recognition in the art scene in 2000, a turf war broke out with some graffiti artists referring to the unoriginal street art that appeared in its wake as done by "art fags."

The artist Banksy was a turning point in the commercialization and popularization of street art, although the messages of his work stand for the opposite message - for independent political content. His breakthrough in the institutional art world (as seen here in 2009 the Bristol City Museum, in his hometown), was celebrated by some and harshly criticized by others.

The first painting by Banksy took in nearly double the expected price when auctioned by Sotheby's in 2005. Celebrity collectors like Brad Pitt brought the artist to his high point of prominence when three years later, the first Banksy to sell for over $1 million occurred. Galleries now display images by Banksy and his contemporaries, like STIK, with or without the artist's permission.

Street art is beloved by city tourists in the age of the selfie. Along with the obligatory visit to Berlin's East Side Gallery, tours through Germany's capital city that focus on street art highlights have become quite popular. In the meantime, other cities have caught on to the trend and begun to offer these tours as well.

Nearly every middle-sized city in Germany has got its own urban art gallery. Relatively new, however, are infotainment events like the magic city series, a large event sold as something "for the whole family." Last held in Dresden, the event moves to Munich for 2017. But the question remains: street art as family entertainment? Would that make sense to its founders?