Classification Web Library of Congress
Searching LC Subject Headings
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Searching Unstructured Subject Headings
In the Unstructured subject heading search the -- (dashes) between the terms are optional. Like the Structured subject heading search, the Unstructured subject heading search is left-match with automatic truncation.The big advantage over the Structured subject heading search is the ability to enter terms freely, without regard to the structure of a Library of Congress subject heading. However, the browse list that Class Web returns is sorted alphabetically, word by word. This means that phrase headings are interfiled with headings that are constructed with subfields.

In this simulation, we have entered the terms "computer aided instruction" in the Unstructured subject heading box. Select the Search button to see that we were redirected to "Computer-assisted instruction" which is used for (UF) "Computer-aided instruction." Next select the Browse button below to see the terms listed alphabetically. Finally, select the Reset button to to see a comparison of structured verses unstructured subject searching.

Select the circled Search button Select the circled Browse button Select the circled Reset button Select the circled Search button

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