||This work analyzes the impact of investments in information and communication technologies (ICT) at the level of states, firms and households. Its contribution lies in the transparency of theoretical views of the role of ICT at the respective levels of the economy and also in the form of an econometric model studying the impact of ICT investments on GDP. The work describes some causes of ambiguous impact of ICT on statistical tables and then uses the Cobb-Douglas production function to define the components of economic growth (represented by GDP). The numerical contribution of each factor is compared between the USA and the EU throughout the periods 1980-1995 and 1995-2001. The look on companies is focused mainly on the role of ICT use in work process and its impact on the economic operation of the companies. To what extent are these firms affecting employment and wages is the main theme of the section related to households. The work showed that very similar procedures are necessary for all of the aforementioned levels of the economy for the desired result of ICT investments. An empirical analysis of 20 European countries during the period 2003-2008 proved positive impact of ICT investments on GDP. The results of the model, however, served more evidence of the significance of the ICT sector.