The development of a quantum computer will have a major impact on our lives. First, scientists have to rewrite many existing cryptographic algorithms and thus redevelop all associated programs, applications, websites, and media. Second, besides a great decryption capacity, quantum computers will have other uses: for example, to describe the properties of materials that specialists cannot calculate with normal devices, or to search for new drugs. The capabilities of a quantum computer will require a breakthrough in all areas of technology, as well as an understanding of aspects of theoretical physics that scientists cannot yet solve due to limitations in computing resources.