The British National Corpus (BNC) is a 100-million-word text corpus of samples of written and spoken English from a wide range of sources. The corpus covers British English of the late 20th century from a wide variety of genres, with the intention that it be a representative sample of spoken and written British English of that time. It is used in corpus linguistics for analysis of corpora.
History
The project to create the BNC involved the collaboration of three publishers (with the Oxford University Press as the lead collaborator, Longman and W. & R. Chambers), two universities (the University of Oxford and Lancaster University), and the British Library. The creation of the BNC started in 1991 under the management of the BNC consortium, and the project was finished by 1994. There have been no additions of new samples after 1994, but the BNC underwent slight revisions before the release of the second edition BNC World (2001) and the third edition BNC XML Edition (2007).
The BNC was the vision of computational linguists whose goal was a corpus of modern (at the time of building the corpus), naturally occurring language in the form of speech and text or writing that could be analyzed by a computer. Hence, it was compiled as a general corpus to pave the way for automatic search and processing in the field of corpus linguistics. One of the ways the BNC was to be differentiated from existing corpora at that time was to open up the data not just to academic research, but also to commercial and educational uses.
The corpus was restricted to just British English, and was not extended to cover World Englishes. This was partly because a significant portion of the cost of the project was being funded by the British government which was logically interested in supporting documentation of its own linguistic variety. Because of its potentially unprecedented size, the BNC required funds from the commercial and academic institutions as well. In turn, BNC data then became available for commercial and academic research.
Description
The BNC is a monolingual corpus, as it records samples of language use in British English only, although occasionally words and phrases from other languages may also be present. It is a synchronic corpus, as only language use from the late 20th century is represented; the BNC is not meant to be a historical record of the development of British English over the ages. From the beginning, those involved in the gathering of written data sought to make the BNC a balanced corpus, and hence looked for data in various mediums.
Components and content
90% of the BNC is samples of written corpus use. These samples were extracted from regional and national newspapers, published research journals or periodicals from various academic fields, fiction and non-fiction books, other published material, and unpublished material such as leaflets, brochures, letters, essays written by students of differing academic levels, speeches, scripts, and many other types of texts.
The remaining 10% of the BNC is samples of spoken language use. These are presented and recorded in the form of orthographic transcriptions. The spoken corpus consists of two parts: one part is demographic, containing the transcriptions of spontaneous natural conversations produced by volunteers of various age groups, social classes and originating from different regions. These conversations were produced in different situations, including formal business or government meetings to conversations on radio shows and phone-ins. These were to account for both the demographic distribution of spoken language and those of linguistically significant variation due to context.
The other part involves context-governed samples such as transcriptions of recordings made at specific types of meeting and event. All the original recordings transcribed for inclusion in the BNC have been deposited at the British Library Sound Archive. The majority of the recordings are freely available from the Oxford University Phonetics Laboratory.