The zipper is a wonderful invention. How did people ever live without zippers? They are very common, so we forget that they are wonderful. They are very strong, but they open and close very easily. They come in many colors and sizes. In the 1890s, people in the United States wore high shoes with a long row of buttons. Clothes often had rows of buttons, too.. People wished that clothes were easier to put on and take off.
A zipper has three parts: 1) There are dozens of metal or plastic hooks (called teeth) on two rows.
2)These hooks are fastened to two strips of cloth. The cloth strips are flexible. The bend easily.
3) A fastener slides along and joins the hooks together. When it slides the other way, it takes the hooks apart.
Dr. Sundback put the hooks on strips of cloth. The cloth hold all the hooks in place. They don't come apart very easily. This solved the problem of the first zippers.
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