Contemporary graffiti art began with tagging or scratching names on public places in New York City, USA in the late 1960s and evolved during the 1970s and 1980s into the creative spray painting of words and images. Graffiti conveying political and social attitudes evolved into beautiful public mural art.For many years a famous icon of repression, the Berlin Wall became one of the world’s largest canvases for anonymous street artists to express their freedom. Since its official opening on September 28, 1990, artists from 21 countries have contributed to the Wall’s display of colorful art works about freedom, peace, world unity, historical events, environmental protection, and other subjects.In recent years, street art has been used to decorate and beautify communities and the surrounding environment. Street art that creatively interacts with elements of nature helps to brighten up dull aspects of city life. “Tree Afro” is a style of street art that complements the trees in a neighborhood, using them to form the hairstyle for a drawn person.Originating in Italy during the 16th century, chalk art began when artists honored the Lady Madonna by using chalk to render Her image on city streets. Contemporary chalk art has three categories of practitioners: copyists who recreate famous art works, free artists who create their own original art, and 3-D artists who use perspective to create 3-D artworks.In this urgent time, street art is becoming an increasingly popular medium used to raise awareness about the climate and the environmental crisis. Many street artists are joining the force to save our planet. In Kreuzberg, Italian street art legend Blu painted a large mural entitled “Global Warming Hourglass” to call attention to melting glaciers and rising sea levels. Street art is also a popular tool for vegan activists to champion animal rights and promote the compassionate lifestyle, which ultimately leads to world peace. London-based vegan artist Louis Masai paints colorful murals of beautiful animals to raise awareness about the plight of endangered species nearing extinction.