A contest is a rivalry between a number of participants for some resources, awards or changes in social status. Contests are a great tool that is used to motivate people to gain higher results and to monitor training and learning progression. Contests are also a popular marketing tool. Coding contests are an old and trusted type of event that is used by most IT and fintech companies and even startups. Blockchain companies often hold coding contests to draw the attention of skilled developers to their products. For most of companies, hacking contests are a great tool for monitoring their vulnerabilities and looking for new specialists. Cryptocurrency contests often include such competitions as cryptography contests and competitive programming. Such crypto contests are useful for marketing and for HR purposes.