NS and NNS
The terms Native Speaker (NS) and Non-Native Speaker (NNS) are used to describe people (often teachers) who have English as an MT or have learnt English as a Second Language respectively.
A native speaker is someone who learned their first language when they were children. They naturally express themselves in that language, they think in that language, and even dream in that language.
So, for example, a native English speaker is somebody whose first language is English. They are usually from English-speaking countries, like Ireland or New Zealand.
The term native speaker is often used as a benchmark for knowledge of a language and as a criterion for employment.
However the definition of native speakers is not clear cut and it raises a lot of opposition when it comes to defining precisely who native and non-native English speakers are. Because of this, linguists have tried to redefine the term so that it can take into account the different varieties of the language and of its users.
There are about 375 million native speakers of English located mainly in the USA, Great Britain, Australia, Canada, Ireland, South Africa and so on. Compare this with over 1.5 billion NNS of English located right around the world.
Some people also use the term Near-Native Speaker meaning someone who speaks English to such a high level of proficiency that they are virtually speaking as a Native Speaker would.
