Android Code-39 Generator
Barcode Code-39 Generation in Android
Code 39 (also known as "USS Code 39", "Code 3/9", "Code 3 of 9", "USD-3", "Alpha39", "Type 39") is a barcode symbology that can encode uppercase letters (A through Z), digits (0 through 9) and a handful of special characters like the $ sign. The barcode itself does not contain a check digit (in contrast to, for instance, Code 128), but it can be considered self-checking by some, on the grounds that a single erroneously interpreted bar cannot generate another valid character. Possibly the most serious drawback of Code 39 is its low data density: It requires more space to encode data in Code 39 than, for example, in Code 128. This means that very small goods cannot be labeled with a Code 39 based barcode. However, Code 39 is still widely used and can be decoded with virtually any barcode reader. One advantage of Code 39 is that since there is no need to generate a check digit, it can easily be integrated into existing printing system by adding a barcode font to the system or printer and then printing the raw data in that font.
The name Code 39 is derived from the fact that three of the nine elements that constitute a codeword are wide elements, the remaining six are narrow. Code 39 was developed by Dr. David Allais and Ray Stevens of Intermec in 1974. It was later standardised as ANSI MH 10.8 M-1983 and MIL-STD-1189.