Pidgins and Creoles
When people who speak different languages and do not share any common language come into contact in a certain area, they sometimes create a very simplified language for the purpose of very basic communication. This is called a "Pidgin". Pidgins developed in a variety of situations. They include trade, where traders from different nations have occasional contact with one another and need just a basic form of communication. Another setting in which pidgins have developed was slavery. Slaves were often deliberately forced to work in mixed groups of people who spoken different African languages, in order to prevent them from communicating effectively with one another (and so preventing revolts).
Usually, a single dominant language contributes most of the vocabulary of the pidgin; we call this the "lexifier" language, since it provides the "lexicon" of the new language. But the grammar of that dominant language is usually ignored. Sometimes, the native languages of the various speakers influence the shape of the grammatical structure of the new pidgin. Generally speaking, pidgins have very simple grammars. They are based largely on a context-bound interpretation of words.
If the pidgin develops more complex linguistic structures and vocabulary, and is used in a wider range of communicative contexts, then it is then called a "Creole". In Linguistics, "Creole" is a technical term for a type of language; it is not connected to the ethnic, racial, or cultural designation as used by some people. For linguists, "Creole" simply means a language that has developed from a pidgin, and has become more widely used and more complex. Having native speakers - that is, a generation of children who grow up speaking the pidgin as their first language - is often considered a central factor in identifying creoles.