人的皮肤由表皮、真皮和皮下组织三部分组成。指纹就是表皮上凸起的纹线。由于人的遗传特性,虽然指纹人人都有,但各不相同。伸出你的手仔细观察,就可以发现指纹也分好几种类型:有同心圆或螺旋形纹线,看上去像水漩涡的,叫斗型纹;有的纹线是一边开口的,就像簸箕似的,叫箕型纹;有的纹像弓一样,叫弓型纹。据说,全世界50多亿人,还没有发现有两个指纹完全相同的呢。正因为指纹的这一特性,它很早就引起了人们的兴趣。在古代, Human skin from the epidermis, dermis and subcutaneous tissue composed of three parts. Fingerprints are raised lines on the epidermis. Due to human genetic characteristics, although fingerprinting has all, but different. Extend your hand carefully observed, you can find fingerprints are divided into several types: a concentric or spiral lines, looks like swirling water, called bucket pattern; some lines are open on the side, it Like a dustpan like, called Kei type pattern; some lines like the bow, called the bow pattern. It is said that more than 5 billion people in the world have not found two identical fingerprints yet. Because of this feature of fingerprints, it has long been of interest to people. In ancient times,