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   "Pictogram" is a compound word made from "picture" and "telegram".Pictograms are usually simple pictures, and they are often made with letters and words.A pictogram is a symbol which represents an idea or an object through an image (图像). Also, it is a kind of communication system which must be learned but is very useful in our lives. The user must learn to see, understand and remember the different pictogram symbols. There are about l, 400 different symbols at the present time.

    A Canadian named Subhas Maharaj came up with the idea for pictograms in the beginning of the 1980s. At first, pictograms were introduced to help people who had disabilities in speaking, reading, or writing. Pictograms are images of objects that are easy to see and create. Today, pictograms are used in many different ways. FOR example, there are traffic, recycling and restaurant signs, even animal symbols and so on.

    Pictograms are usually in white against a black background. The combination of white against a black background creates extremely contrast (对比) , and this makes pictograms friendlier to users. A good example of a pictogram is the public toilet symbols for "men" and women", just like the one on the left. Pictograms are a useful method of communication, and people can have fun as they learn each pictogram.