Cryptography in modern life, web application security

Everyone is aware of the role of the Internet in today's life of the people. This is the best way of communication, information sharing, getting education and to obtain the desired information. Today almost every field of activities requires presentative or informational web pages, to make it possible to society to access information eassily, including information about their practice and activities. Also it's notable how the usage of social networks, portals (in which user's personal information are stored) increases. Even all the human activities and works became mostly dependent on the computer and internet. Different organizations are actively using online systems for internal staff communication, document exchange, for the distribution of tasks, etc. This saves time and also it makes possible to save all the information aboud activity. This is particularly relevant to the software developing companies. All, that was saied above, shows how the development of information technologye becomes more and more important. And so solving the data protection mechanism issues become more important too. My goal in this article is to reflect the details, list of errors, that a web application programmer might make and pay no attention while developing an application. Also I intend to analyse them, to discuss ways of resolving problems, the reasons for the threat, what kind of attacks are possible and how they can bring damage. Kriptograpiis use in this way will help us to avoid undesirable surprises and possible access to the information of another person. We are showing how important it might become, to minimalise he's access of the application, information transmission, storage. External person (the attacker) can: Change Site Content. Embed a spam link and redirect the user to another site. Embed dangerous code, which will be installed on the visitor's computer. Embed code, which steals user's current session identificator (username, password). Steal the visitor's personal information. Steal user account information. Steal information stored in the database And much more ...