Street art started out as unintelligible words written on concrete walls with spray paint by gang members or silly kids. Now, however, it evolved into a unique form of art that might stun and inspire awe in the onlookers. For example, the artist that goes by the name 1010 specializes in creating optical illusions. His creations look like portals into other dimensions, without any hint that it might simply be a flat concrete wall painted over with multicolored paints. These pieces of art are so good that it is hard not to reach out into these ‘holes’ to find out whether or not they are real. (Photo by 1010)

Suso33 spent the last few days perched on a yellow crane to work on this impressive new piece on the streets of Madrid, Spain. Using a rather simple technique, the Spanish artist painted a brilliant piece which enters directly amongst our favourite artworks this year. This mural is a concentration of slightly outlined figures which are persecuted by their shadows, but if the viewer, instead of focusing on details, looks at the entire picture, what he sees is another figure. Take a look at more images after the jump and if you are in the area, you'll be able to find the piece at plaza del Poeta Leopoldo de Luis.

Born in Los Angeles in 1980 to an engineer and an artist, Mac has been creating and studying art independently since childhood. He was inspired at a young age by classic European painters such as Caravaggio, and Vermeer and Art Nouveau symbolists such as Klimt and Mucha. This was mixed with the more contemporary influences of graffiti and photorealism, as well as as the Chicano & Mexican culture he grew up around.

French street artist OakOak produces creative works of art that use the characteristics of a location such as a light post, road sign and even a crack in the wall as inspiration but also as key elements in the work. (Photo by OakOak)

The giant mural titled “Under the Hand” by Maclaim Crew is visible on a building facade in Kreuzberg district on June 26, 2014 in Berlin, Germany. Berlin, with its long tradition of counter-culture, has become a mecca for street art of all dimensions and messages. (Photo by Sean Gallup/Getty Images)

Artist Julien “Seth” Malland aka Seth Globepainter has become known around the world for his vibrant murals of people, most frequently children, who appear to be sucked into colorful rainbow-like voids. The figures are usually facing away from the viewer, their attention completely swallowed by pools of dripping color revealed behind drab, urban facades.

Iranian artist and designer Mehdi Ghadyanloo, with the help of the municipality, is slowly brightening up the city of Tehran one wall at a time. The 33-year old street artist has been painting murals and walls in Tehran for the last 5 years age, during which he’s reported to have painted over one hundred walls.