BSL has many regional dialects. Certain signs used in Scotland, for example, may not be understood immediately, or not understood at all, by those in Southern England, or vice versa. Some signs are even more local, occurring only in certain towns or cities (such as the Manchester system of number signs). Likewise, some may go in or out of fashion, or evolve over time, just as terms in oral languages do. Families may have signs unique to them to accommodate for certain situations or to describe an object that may otherwise require fingerspelling.