The origins of the English dictionary are found in the late 16th cent. when people became aware of the two levels of English (‘learned’, ‘literary’, ‘inkhorn’, distinct from ‘spoken’, ‘popular’) to an extent that made it desirable to gloss one in the other's terms. Cawdrey's Table Alphabeticall of Hard Wordes (1604), containing about 3,000 words, might be called the first English dictionary; Henry Cockeram's English Dictionarie (1623) translates hard words to easy as well as easy to hard. The first major English dictionary was N. Bailey's Universal Etymological English Dictionary (1721). Dr Johnson's Dictionary (1755) is one of the two great landmarks in English lexicographical history; Johnson illustrates his words in practice, and attempts to indicate the connotations of words, as well as offering their exact meaning. The second great landmark is the greatest dictionary of any modern language, The Oxford English Dictionary (1884–1928), edited by J. A. H. Murray, H. Bradley, W. A. Craigie, and C. T. Onions. The OED attempts to give a full history of the development of all English words since the 12th cent., with full illustrative quotations, ordered according to the principal distinct senses of the word. It has been updated by a series of supplements under the editorship of R. W. Burchfield. The possibility of a dictionary organized on synchronic, rather than historical, principles was brought closer when in 1984 the OED files began to be converted into a computerized database. The other major English language dictionary is N. Webster's dictionary of American English (1828; Third New International Dictionary, 1961), the Third being controversial on its appearance for its omission of indications of inferior usage in categories such as ‘slang’, ‘obscene’, etc.