EN
Information is very important in every activity of a company. For this reason using Internet to search for the information has quickly increased. This paper discusses a very important issue of the Internet-based information – its trustworthiness. It describes difficulties, which are encountered during information trustworthiness verification, and evaluation methods, which have been developed. The paper presents also two ontologies to verify Internet-based information trustworthiness. The first one, created by Fox and Huang, focuses on knowledge provenance. In this ontology there are two things in which pressure was put on: an author and a reproduction of information in other sources. It also considers two aspects: time and uncertainty. The second of described ontologies was created by the paper's author. It was built by adapting historians methods to verify the information. The paper also contains similarities and differences in presented ontologies.