The expansion of information and communication technology (ICT) use in society has conducted an intense movement of inclusion is nevertheless on accessibility has also presented paradoxically notable exclusion of important social groups. This paper presents eyeliners aspects of Web accessibility as a major factor of social and digital inclusion particularly the senior population. Establishes the epistemological approach between sociology and informatics, scientific fields that leverage alternative whose prospects are promising solution to the problem of the digital divide. Based on two studies that manage to know the behavior of the Portuguese senior next to ICT and the improvement of benefits to this social layer when the quality standards meet international accessibility recommendations emerging. Identifies some gaps between the recommendations made by international bodies and professional developers of Web systems; and what has been the cause of this growing exclusion of senior users and others that are achieved by this omission.