Graffiti has appeared at least since the days of ancient civilization
Currently, there are seven common styles of graffiti that can be listed: tag, throw-up, piece, wildstyle, blockbuster, get-up and stencils. Firstly, a “tag”, the most basic writing, is a graffiti writer’s personalized signature which is written in either spray paint or marker.
Secondly, “throw-up” (or “fill-in”) is normally painted very quickly with two or three colors, sacrificing aesthetics for speed. An artist can also use only one color to outline it on a surface.
Thirdly, a “piece” is a more elaborate image of the artist’s name, incorporating more stylized “block” or “bubble” letters and using three or more colors.
Next, a more complex style is “wildstyle” consisting of interlocking letters, arrows, and conecting points. As the letters merge into one another in an often undecipherable manner, it is harder to read by non-graffiti artists.
Another form should be mentioned is “blockbuster”. In other words, it is a “fill-in” that intentionally takes up an entire wall, sometimes in order to prevent other “taggers” from painting on the same wall.
Another common form of graffiti is “get-up” using stickers. With 5 to 10 minutes spent on a detailed sticker, the supporters of this form suppose that it is in no way lazy and a form of cheating as the opponents consider. Sticker tags are commonly done on blank postage stickers, or really anything with an adhesive side to it.The last form, "stencils" are made by drawing an image onto a piece of cardboard or tougher versions of paper, then cut with a razor blade. What is left is then just simply sprayed-over, and if done correctly, a perfect image is left.
Sources:
Information is taken from wikipedia wikipedia
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