It is known as dialect to the linguistic system which derives from another but does not exhibit sufficient differentiation from others of common origin. Dialects, therefore, are usually considered in relation to a set of several linguistic systems of a common trunk or that are in the same geographical boundary. Another definition of dialect refers to the linguistic structure that does not reach the social category of language .

The dialects are linked to the linguistic variety and, therefore, to the linguistic diversity . Although the dialect is usually considered as a kind of system Of a lower category or simpler than a language, dialects are, in fact, particular ways of speaking or writing a certain language.
It is interesting to establish and also know that, in a usual way, there are a series of criteria to differentiate a dialect. In this sense, it should be noted that among them is the fact that it does not have a written tradition, it does not have too many grammatical differences with respect to the dominant language, those who speak said dialect do not have a nation of their own and also that their speakers They are usually few.
All this without forgetting that the term dialect is frequently used with a marked pejorative sense, since it is considered that it is “inferior” to the official language and that it basically demonstrates the lower social or cultural importance of those who speak it regularly. .
In the case of Spain we find the fact that there are two clearly differentiated groups of dialects. Thus, on the one hand, there are the northern ones, which are the ones spoken in the northern half of the country, and on the other hand there are the southern ones, which are the ones used in the southern half of the nation.
Examples of the first case are Asturian, Castilian Rioja or Castilian Churro, which is what is present in the Valencian Community area.
In the second case, that of the southern dialects, we find examples of great importance such as the case of the Madrid dialect, characterized by Yeism, seism, leism or loism. Likewise, another of the most important dialects is Andalusian, which has a great variety in matters of vocabulary of Mozarabic, Roma or Arabic origin.
In this sense, dialects can arise by geographical variety. In the case of Spanish, for example, the dialect spoken in Spain use words like "computer" or "Matches", Meanwhile in Latin America those terms are not used (they are replaced by "computer" and "Matches").
The specialists talk about prestigious dialect to refer to the dialect chosen by the most prestigious people or who belong to the highest social classes in a community of speakers where several dialects co-exist.
In general, three criteria are taken into account to consider whether two linguistic systems are independent dialects or languages: dialects must be mutually intelligible without prior learning, must be part of a politically unified territory and must have a common writing system.