Intelligent Mail Barcodes
Intelligent Mail bar codes are an improved version of POSTNET bar codes. They're used to sort and track mail as it's delivered around the country and the world. Intelligent Mail provides more detailed information than POSTNET, though, as it encodes the sender's information in addition to the recipient's.
Specifications: Like POSTNET, Intelligent Mail is encoded based on bar height, rather than by bar and space width, like most other bar codes. However, the distance between the bars also is a factor in Intelligent Mail's encoding. The bar code has a total of 65 bars, which can encode up to 31 digits of data.
Advantages: Intelligent Mail is more accurate and efficient than POSTNET, and as such, is in the process of replacing it entirely.
Disadvantages: Intelligent Mail is still significantly longer than an ordinary bar code, and requires many more characters than the data that it's encoding. Additionally, it's limited to 31 characters of data, and only includes numbers, not letters or any other characters.
Related Bar Codes:
POSTNET: The predecessor to Intelligent Mail, which is now on its way to becoming obsolete. POSTNET also encodes data by bar height, however, the bar code must always be more than five times the length of the actual data encoded.