2 of 5 Code
Interleaved 2 of 5 code is a numeric only barcode. Each character of this code is represented by five elements, two wide and three narrow. Wide elements are decoded as binary one (1), and narrow elements are decoded as binary zero (0). The wide to narrow element ratio should be between two and three.
Whether or not the elements used to encode a character are bars or spaces depends upon the location of the character within the message. The first character of the message is encoded into the bars immediately following the start character. The second character of the message is encoded into the spaces between the bars of the first character, thus eliminating the intercharacter space. Because of this, Interleaved 2 of 5 is a continuous barcode.