The first association on the word "data" for common man is a visualization of the alpha-numeric characters and various pictures in the form of a table or chart. Distinction between data, information and knowledge, is one of the primary tasks of information science. The quantity of electronic data in today's information society is steadily increased by using Internet technologies (among other things with the e-government and all it's parts-from commerce, education to public health, also with the emergence of social networks and media in all their forms). It requires visualization of the data for easier understanding and analysis which are obviously necessary. In this paper some of the commercial and non-commercial visual tools and their application in analysis of social networks are considered, with especially interest for theirs application in the field of criminology.