Plain-language explanation.
Applied linguistics uses insights from the scientific study of language to solve real-world language problems. It includes helping people learn foreign languages, training translators and interpreters, improving literacy education, and advising on language policies that affect multilingual communities.
Core concepts and standard treatment.
Applied linguistics encompasses: second language acquisition (SLA) and language pedagogy (how people learn and should be taught additional languages — communicative language teaching, task-based language teaching, content and language integrated learning), translation and interpreting (equivalence, domestication vs. foreignisation, simultaneous interpreting cognitive demands), discourse analysis (analysing language use in institutional, professional, and media contexts), and literacy studies (reading acquisition, multiliteracies, digital literacy).
Deeper theory, debates and edge cases.
Language teacher education integrates SLA research with pedagogy: the interface between implicit and explicit language knowledge, corrective feedback types (recasts, elicitation, explicit correction), focus on form vs. focus on meaning, and the role of output and interaction in language development. Corpus linguistics tools (concordancers, frequency lists, collocation analyses) inform materials development and lexicography. Translation technology — CAT tools (translation memory, terminology management), post-editing of machine translation — is transforming professional translation practice.
How it is applied in practice.
Language policy and planning in applied linguistics: English as a Lingua Franca (ELF) research challenges native-speaker norms as pedagogical targets; World Englishes framework recognises institutionalised varieties (Indian English, Singapore English) as legitimate linguistic systems. Heritage language education policy balances assimilation and maintenance goals. Critical applied linguistics (Pennycook) examines power, ideology, and inequality in language education and policy contexts. Literacy assessment design draws on applied linguistics for construct validity, item difficulty modelling, and fairness across language backgrounds.