4.1 Name coding. The idea behind a coding system is that the resulting code may be generated by a set of rules, i.e., an algorithm. The system takes each and every spelling and translates it letter-by-letter, or by letter combination, to a particular name code. Thus various spellings may end up with the same code, with the intent that variants of the same name receive the same code. This is the more popular method to treat the errors arising directly from the spoken and written language, and particularly when the names are handwritten. There is an introduction to the details of certain widely used coding rules below in ¶¶2, 3, 4. They are built on certain design principles.

Linguists call rules that are designed to characterize words by their sound when spoken morpho-phonemic. The term morpho- refers to the meaning-carrying portion of a word. The term phonemic relates to the conceptual structure of the linguistic sound. This is just a fancy way of saying that the language of the name imposes certain structures on the words that help to make them intelligible when pronounced. The native speaker sometimes hears different sounds as though they were the same sound. Often the language promotes this by allowing the speaker different options in producing the sound. In any event, there is always some equivalence that will be perceived by some to be different. And by the same token there will be some differences that a hearer will perceive to be the same.

The rules are called rewrite rules. The form of a rewrite rule is as follows where each Greek letter stands for an arbitrary string of characters to be specified in the rule:

The letter alpha stands for the sequence of characters to be rewritten. The letter beta stands for the sequence of charaters that are to replace alpha due to the effects of the rule. The psi stands for the sequence of characters that must precede alpha as a condition on its execution. The phi stands for the sequence of characters that must follow alpha as another condition on its execution. Another way of writing this formula is as follows:

It is further understood that such a rule affects all sequences of psi-alpha-phi that appear in a string, so that all alpha that fit the environment get replaced by beta. The rules are then ordered so that after a rule has executed on all valid portions of the string, the next rule executes. There are more details concerning rewrite rules below in Chapter 4, §3.