Lexicographic tools are tools that people use when they need to solve language problems,particularly problems related to vocabulary, i.e. lexis. They are typically used by two groups ofpeople: on the one hand, professionals working in the various disciplines within Linguistics usethem; on the other, dictionaries and related lexical databases play an important role in learningforeign languages. Nevertheless, most people have used some kind of lexicographic tool in their lives,for instance, in order to look up the meaning of a word in a dictionary or find some information on atopic in an encyclopaedia.The adjective lexicographic is related to the names of two linguistic disciplines: lexicology andlexicography. Both terms come from the Greek word lexiko meaning ?speech?, ?way of speaking? or,simply, ?word?, which suggests that these disciplines are closely related. However, they are not thesame: lexicology is a theoretical discipline focused on the study of words, and lexicography is apractical discipline that deals with the concrete forms of words, that is, words as they appear indictionaries and other lexicographic tools. In other words, lexicology provides the theoretical basisfor lexicography and lexicography may be seen as applied lexicology.