- monolingual dictionaries are written in one language and give explanations for words in that language. Most available monolingual dictionaries are made with the native speaker in mind. For EFL students a monolingual learner's dictionary is recommended.
- bilingual dictionaries give the translation for words in one language into another language.
Students of English should - in an ideal world - possess both types of dictionary and be fluent in their use. Electronic dictionaries and the internet have replaced the traditional paper dictionary for many users.
With the advent of information and communication technology (ICT) in the late 20th century it became possible to manipulate and process very large texts, especially useful in building up corpora, or corpuses like the Oxford English Corpus, thus greatly adding to the amount of information available to lexicographers, teachers, etc.
A new branch of lexicography, that of corpus lexicography, has also evolved as a result.
Online monolingual dictionaries
- Collins online English dictionary
- Merriam-Webster Online
- Oxford Dictionaries
- Oxford Language Dictionaries Online
- Oxford Learner's Dictionaries. Definitions use only the most useful 3000 English words.
- The English Dictionary
- RapiDefs.com, unique user interface
Online bilingual/multilingual dictionaries
- Collins online bilingual dictionaries
- Wordreference Combination monolingual dictionary, multilingual dictionary, phrase translator and thesaurus.
- Collins Dictionaries
- Macmillan Dictionary
- Oxford English Dictionary