A dialect is the variety of language spoken by people in a particular region or group. Usually a dialect can be identified by thoroughly analysing its phonology (for spoken dialects), lexicon and, to a lesser extent, its syntax.
Even in languages with small populations, such as Mato /[met] with only 600 people, there can be dialects. Thus, in any language with a sizeable population there will be dialects.
Determining the difference between a language and dialect is one of the longest running debates in linguistics. One of the reasons for disagreement is that how you distinguish them depends largely on what your purpose is in defining the terms. For example, in SIL's catalogue of the world's languages, Ethnologue, the organisation defines language and dialect according to their purposes as a language development organisation with a focus on respecting ethnolinguistic identity, thus:
- Two related varieties are normally considered varieties of the same language if speakers of each variety have inherent understanding of the other variety at a functional level (that is, can understand based on knowledge of their own variety without needing to learn the other variety).
- Where spoken intelligibility between varieties is marginal, the existence of a common literature or of a common ethnolinguistic identity with a central variety that both understand can be a strong indicator that they should nevertheless be considered varieties of the same language.
- Where there is enough intelligibility between varieties to enable communication, the existence of well-established distinct ethnolinguistic identities can be a strong indicator that they should nevertheless be considered to be different languages.<ref>Lewis, Paul. Ethnologue. 16th Edition. Edited by Paul Lewis. Dallas: SIL, 2009.</ref>