English as a second or foreign language is the use of English by speakers with different native languages, often with students whose native language is not English and are learning to speak and write English, commonly among students. Language education for people learning English may be known as English as a foreign language (EFL), English as a second language (ESL), English for speakers of other languages (ESOL), English as an additional language (EAL), or English as a new language (ENL), which refers to the practice of studying English in a country where it is not the dominant language. These programs, especially ESL, are usually an academic subject, course, or program designed to teach English to students who are not yet proficient in the language. While some people only refer to learning in an English-speaking country, learning this language can also entail learning in a non-English speaking or non-native nation.

The term Spanish as a second or foreign language is the learning or teaching of the Spanish language for those whose first language is not Spanish.