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Greentext is usually used for quotation and storytelling.
This began on the *chan imageboards, where quoting text places a > in front of it, turning it green. This effect can also be done manually. Before long, this feature was put to innovative use. When quoting another post, greentext is frequently used for summary, criticism, and ridicule. Its other major use is storytelling, in which a lengthy story is told through fragmentary statements in greentext.