Explanation of "Language Clusters"
Linguists group languages together because they are similar to various degrees. These similarities are due to the historical development from an earlier "parent" language. One such grouping, called "genetic classification," is found in "Ethnologue: Languages of the World" (www.ethnologue.com).
When working on one language, we can learn much from what is already known from other related languages. For this reason and to facilitate language development, SIL Cameroon is grouping languages together into "clusters." These clusters are based not only on linguistic similarity, but also on practical considerations that make working with several language communities at the same time easier, such as geographic distance, ease of travel, common language of communication, etc.