A two-dimensional code having a rectangular region delineated from a background by a single border consisting of a plurality of border lines , comprising: code blocks (10 ) each composed of a plurality of cells (C)which are aggregated, each of the cells (C) having a predetermined size; a first specific pattern configured to specify the positions of the cells (C), a second specific pattern configured to distinguish the code blocks (10 ) from the background of the code; and a pattern insertion area , wherein the code blocks (10 ) and the first specific pattern pattern , the second specific pattern 143, 144), and the pattern insertion area are arranged in the rectangular region, the first specific pattern is located at a designated corner of the rectangular region, the second specific pattern is located along one or more of first border lines along which the first specific pattern is located, the first border lines being part of the border lines of the rectangular region, the code blocks (10 ) include error-correction code blocks for correcting an error of blocks of codes of data being decoded, the pattern insertion area is arranged in an area other than the second border lines in the rectangular region, a pattern different from the cells is arranged in the pattern insertion area, characterized in that the error-correction code blocks are located, at least, along second border lines of the border lines , the second border lines being other than the first border lines in the border lines , and in that the pattern insertion area is larger than the size of each of the cells and is provided as an area configured by a plurality of cells composing part of the code blocks, the plurality of cells composing the part of the code blocks being other than the cells composing the error-correction code blocks located, at least, along the second border lines . code blocks (10 ) each composed of a plurality of cells (C)which are aggregated, each of the cells (C) having a predetermined size; a first specific pattern configured to specify the positions of the cells (C), a second specific pattern configured to distinguish the code blocks (10 ) from the background of the code; and a pattern insertion area , wherein the code blocks (10 ) and the first specific pattern pattern , the second specific pattern 143, 144), and the pattern insertion area are arranged in the rectangular region, the first specific pattern is located at a designated corner of the rectangular region, the second specific pattern is located along one or more of first border lines along which the first specific pattern is located, the first border lines being part of the border lines of the rectangular region, the code blocks (10 ) include error-correction code blocks for correcting an error of blocks of codes of data being decoded, the pattern insertion area is arranged in an area other than the second border lines in the rectangular region, a pattern different from the cells is arranged in the pattern insertion area, characterized in that the error-correction code blocks are located, at least, along second border lines of the border lines , the second border lines being other than the first border lines in the border lines , and in that the pattern insertion area is larger than the size of each of the cells and is provided as an area configured by a plurality of cells composing part of the code blocks, the plurality of cells composing the part of the code blocks being other than the cells composing the error-correction code blocks located, at least, along the second border lines . <EOS>