KWIC is the abbreviation of Key Word In Context, a technique developed by Hans Peter Luhn in IBM in 1958 to automatically generate indexes, especially for technical-scientific work. This does not include the titles alphabetically, but the "keywords" that appear in it; and these are shown in their context, ie with a number of surrounding words. "Stopwords", such as members, conjunctions, or prefixes are not normally considered "keyword", and not included in indexing.
The technique is also widely used for showing concordances of texts; and (internet) search engines usually show their results in KWIC form; The specified search term is the "keyword". Example
The following image shows a section of a KWIC index for a fictional computer book catalog. The keywords are centrally aligned; In this case the "context" is the rest of the title of the work. The advantage of this technique is clear here: someone looking for books on e.g. Excel, she is all grouped here; while he should complete an alphabetical index completely.
A title containing multiple "keywords" also appears in the index, once for each keyword; See, for example, catalog numbers 900 or 904. A printed KWIC index is therefore several times greater than an alphabetical index: if there are on average four keywords per title, it is four times larger. This is obviously not an objection for online searching.
A KWIC index is also called a permuted index or rotated index. Also see
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