 Because artifacts are typically a loosely structured sequence of words and other symbols (rather than concepts), the problem is nontrivial, but it can provide powerful insights into the meaning, provenance and similarity of documents.Traditionally, the conversion of words to concepts has been performed using a thesaurus, and for computational techniques the tendency is to do the same.The thesauri used are either specially created for the task, or a pre-existing language model, usually related to Princeton's WordNet.