Media information manipulation in the present days has lost its features of an extraordinary, extremely non-ethical and mainly inacceptable banned mean. Information manipulation has been used everywhere where there are for a particular subject no reasons, opportunities, possibilities and means from the view of its particular (utilitarian) interests to purposely influence attitudes, opinions, motivation and behaviour of individuals and social groups. To conclude and to do it gently, it is to be called the manipulation with the public opinion. When examining particular aspects of this issue it is impossible to rely upon the terminology which would be sufficiently complex, in Slovak conditions stable and generally accepted. This fact causes it is impossible to start examining particular problems, as before doing so it is necessary to explain and define the basic points and draw the line of a possible effective approach. The effect of manipulation is the change of an existing or creation of a new evaluating viewpoint and relation of the recipient to something definite what influences (manipulates) its future actions, behaviour, opinions and attitudes. The viewpoint from the aspect of basic information and communication knowledge theory is crucial: if some of the real information systems reach the dominant mass media position and are used as the source of prevailing inadequate or redundant information, logically, instead of processes deepening the composition of information system – such as human consciousness (shaping and development of personality, its autonomy and integrity), it initiates the growth of entropy in mind. It is true that each piece of inadequate information, which is”pressed” on the structure of system, changes it as a whole and from the human viewpoint devalues the system as it weakens its ability to regenerate. Positive, full-value informedness can be achieved only through the exchange of adequate and additive information.