Sign languages, just like spoken languages, have evolved naturally. Sign languages have developed out of human contact within deaf communities; in deaf schools, deaf clubs, etc. Since these concentrations of deaf people took place on a regional level, unique "local" sign languages emerged worldwide, with their own conventional sign language lexicon and their own grammar rules. These different sign languages were later recognised on a national level and most of them are named after the country where the sign language originated, e.g. British Sign Language, Dutch Sign Language and Irish Sign Language. Though, even within country borders there can be several recognised sign languages, like Flemish Sign Language and the French Belgian Sign Language (LSFB). Spain has Spanish Sign Language (LSE) and Catalan Sign Language (LSC).