In terms of localization and also marketing customization of written content (e.g. in catalogs, websites, or promotional material), professional translation providers should be able to adjust the language and its style to match specifics of a region, ethnicity, or even a social group. But what is a dialect to begin with? And how does it relate to a language?
Localizing to dialects vs. localizing to languages
A dialect can be explained in two ways. It can be a subordinate language variant of a regional or national standard / official language, where the variant is, interestingly, not derived from, but related to the dominant language. However, the term dialect is also used to define a variant of a language that is characteristic to a certain group of language speakers. In this point of view, it is actually a matter of a scientific linguistic debate where to draw the border between a dialect and a language. There is also anopinion, that it's not possible to exactly determine where a dialect ends and a language begins. And here we come to the essence of professional and high-quality localization: knowing what language variant and form to use to grasp the essence of the locale. As languages and dialects evolve similar to living organisms, influenced by a number of factors from geographical and social, to historical and political, it is sometimes highly delicate to determine how to translate content to maximize impact.
When dialect is a language and language is a dialect
Yes, dialect and language can mean different things around the world. Let's take Chinese language, for example. All its variants share the same writing system, but in terms of mutual interchangeability e.g. the Cantonese and Mandarin dialects relate similarly as Spanish does with Italian, or Czech with Polish. The same goes for Arabic language and its dialects.
The understanding of a language as dominant over the dialect can also be reversed so that even though the language is considered "standard" or "official", the dialect of the target area or social / ethnic group is emphasized and "wins" over the language. Recognizing that this is an ongoing process, these days often accelerated by political forces, the translation industry needs to react in a flexible way and target evolving dialects, especially those that one day will turn into independent languages.