Fuzzy set theories facilitate the extensions of today's Web structure, especially in the context of Web data. Currently, the increase or sharing of data from different sources: individuals, industries, academia, etc are not knowing/ considering the origin of Semantic Web transition. As the extension of Web grows, the thorny problem of data heterogeneity is also increasing. However, the review/comparability of the fuzzy sets, crisp sets and Semantic Web technologies were given based on their extensions. The authors provided the approaches that will help in knowing the uncertainty within the Semantic Web environment.