Ontology represents knowledge and information not only in the semantic web domain, but in many other domains too, such as the biomedical, construction, business, and the cultural domains. The explosive increment in a number of ontologies has necessitated an ontology storage that can store colossal ontologies. Many ontology storages have been developed till date. However, these ontology storages, which lack management, cause semantic heterogeneity and tend to have low quality. To resolve these problems, several ontology repositories have been proposed to help in the creation, sharing, searching, and management of diverse ontologies.