What are the differences between the terminology and bibliographic codes in the ISO 639-2 standard?
In the ISO 639-2 standard, two code sets are provided in which the language codes are the same except for 22 of the 450+ languages that have alternative codes. One set is for bibliographic applications, often referred to as ISO 639-2/B, and the other for terminology applications, referred to as ISO 639-2/T. The choice of the set used must be made clear by exchanging partners prior to information interchange. These alternative codes in ISO 639-2 exist for historical reasons. At the time that ISO 639-2 was developed, there already was a well-known and widely used language code list that had been used for over 30 years in bibliographic systems which was largely adapted for the 3-character code set . At the same time there was the 2-character code list (now called ISO 639-1, previously ISO 639), which covered far fewer languages than those for bibliographic applications. There was a desire by some participants for the 3-character codes for languages that were already in the 2-character lis
In the ISO 639-2 standard, two code sets are provided in which the language codes are the same except for 22 of the 450+ languages that have alternative codes. One set is for bibliographic applications, often referred to as ISO 639-2/B, and the other for terminology applications, referred to as ISO 639-2/T. The choice of the set used must be made clear by exchanging partners prior to information interchange. These alternative codes in ISO 639-2 exist for historical reasons. At the time that ISO 639-2 was developed, there already was a well-known and widely used language code list that had been used for over 30 years in bibliographic systems which was largely adapted for the 3-character code set . At the same time there was the 2-character code list (now called ISO 639-1, previously ISO 639), which covered far fewer languages than those for bibliographic applications. There was a desire by some participants for the 3-character codes for languages that were already in the 2-character lis
