L2 speakers

A person's second language or L2, is a language that is not the native language of the speaker, but that is used in the locale of that person. In contrast, a foreign language is a language that is learned in an area where that language is not generally spoken. Some languages, often called auxiliary languages, are used primarily as second languages or linguas franca.

More informally, a second language can be said to be any language learned in addition to one's native language, especially in context of second language acquisition, (that is, learning a new foreign language).

A person's first language is not necessarily their dominant language, the one they use most or are most comfortable with. For example, the Canadian census defines first language for its purposes as "the first language learned in childhood and still spoken", recognizing that for some, the earliest language may be lost, a process known as language attrition. This can happen when young children move, with or without their family (because of immigration or international adoption), to a new language environment.

The distinction between acquiring and learning was made by Stephen Krashen (1982) as part of his Monitor Theory. According to Krashen, the acquisition of a language is a natural process; whereas learning a language is a conscious one. In the former, the student needs to partake in natural communicative situations. In the latter, error correction is present, as is the study of grammatical rules isolated from natural language. Not all educators in second language agree to this distinction; however, the study of how a second language is learned/acquired is referred to as second-language acquisition (SLA).

Research in SLA "...focuses on the developing knowledge and use of a language by children and adults who already know at least one other language... [and] a knowledge of second-language acquisition may help educational policy makers set more realistic goals for programmes for both foreign language courses and the learning of the majority language by minority language children and adults." (Spada & Lightbown, p. 115).

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