Spanish language
In Spain and in some other parts of the Spanish-speaking world, Spanish is called not only (Spanish) but also (Castilian), the language from the kingdom of Castile, contrasting it with other languages spoken in Spain such as Galician, Basque, Asturian, Catalan, Aragonese and Occitan.
Language code
For example, most people in Central America and South America speak Spanish. 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 idioms.