A secure web authorization and authentication system

The thesis presents in detail some well-known web applications. I gave a subjective critique which doesn't represent proffesional study, it's just my opinion. The thesis also presents the main features and tools that have been used in the development of my own web applicaton system. Public-key criptography which contains detail presentation of use and structure of digital certificates and differences between symmetric and asymmetric criptography. All login systems, which are mentioned hereafter, have in comon that their communication between client and web server is taking place via secure connection called HTTPS. During the development I came up with idea that the first step to improve the safety would be the implementation of two-factor authentication (TFA), which makes a job difficult to a potential attacker