76 H OW TO S HARPEN Y OUR B USINESS W RITING S KILLS D ICTIONARIES : T OOLS OF THE T RAD E To help you choose the right word and use it properly, the dictionary is an essential reference tool. There you ll find the meaning, spelling, pronunciation, correct usage, and origin of hundreds of thousands of words. Not all dictionaries are created equal, though all will provide you with basic language information. They range in size from huge, unabridged dictionaries to pocket versions, which are compact and portable but considerably less complete. Dictionaries also range in authoritativeness, that is, the qualifications of the people determining what words, definitions, and usage notes are included. For your writing purposes, a desk dictionary the intermediate size is probably best, and of the many desk dictionaries, three stand out: Webster s New World College Dictionary, Random House Webster s College Dictionary, Second Edition, and The American Heritage College Dictionary. Many dictionaries including the multivolume Oxford English Dictionary are available on CD-ROM, which may be a more convenient format for you. These are often packaged with a thesaurus or dictionary of synonyms, and other reference works. It is important to update your dictionary occasionally because our ever-changing language continually erodes the usefulness of older dictionaries. This is especially true in professional and technical language. The publishers of the best dictionaries revise them regularly, so you should get a new dictionary every five or six years and certainly at least once a decade.