Language code schemes attempt to classify the complex world of human languages,
dialects, and
variants. Most schemes make some compromises between being general and being complete enough to support specific dialects. For example,
Spanish is spoken in over 20 countries in North America, Central America, the Caribbean, and Europe. Spanish spoken in
Mexico will be slightly different from Spanish spoken in
Peru. Different regions of Mexico will have slightly different dialects and accents of Spanish. A language code scheme might group these all as "Spanish" for choosing a keyboard layout, most as "Spanish" for general usage, or separate each dialect to allow region-specific variation. == Common schemes ==