二维码 （2-dimensional bar code） 是用某种特定的几何图形按一定规律在平面（二维方向上）分布的黑白相间的图形记录数据符号信息的；在代码编制上巧妙地利用构成计算机内部逻辑基础的“0”、“1”比特流的概念，使用若干个与二进制相对应的几何形体来表示文字数值信息，通过图象输入设备或光电扫描设备自动识读以实现信息自动处理： 二维条码/二维码能够在横向和纵向两个方位同时表达信息，因此能在很小的面积内表达大量的信息。-Two-dimensional code (2-dimensional bar code) is a specific geometry according to certain rules in the plane (two-dimensional direction) distribution of black and white graphic record of the data symbols of information　in the preparation of the clever use of the code constitutes a computer based on internal logic " 0" , " 1"　bit stream of the concept, using the binary number corresponds with the geometric shape to represent the text value of information, through the image input device or the optical scanning device automatically literacy to achieve the automatic processing of information: two-dimensional bar code/two-dimensional code can be both horizontal and vertical directions while the expression of information, so the area can be expressed in a small amount of information.