"Critical Theory has a narrow and a broad meaning in philosophy and in the history of the social sciences. 'Critical Theory' in the narrow sense designates several generations of German philosophers and social theorists in the Western European Marxist tradition known as the Frankfurt School. According to these theorists, a 'critical' theory may be distinguished from a 'traditional' theory according to a specific practical purpose: a theory is critical to the extent that it seeks human emancipation, 'to liberate human beings from the circumstances that enslave them' (Horkheimer 1982, 244). Because such theories aim to explain and transform all the circumstances that enslave human beings, many 'critical theories' in the broader sense have been developed. They have emerged in connection with the many social movements that identify varied dimensions of the domination of human beings in modern societies. In both the broad and the narrow senses, however, a critical theory provides the descriptive and normative bases for social inquiry aimed at decreasing domination and increasing freedom in all their forms" (read the full essay here).
Indeed, the departure effected by critical theory has been revolutionary to say the least, as almost every aspect of human civilization has been put under the intense scrutiny of a new type of reading that has challenged traditionally accepted modes of interpretation. Sometimes referred to as "French Theory," or simply as "Theory," and intimately connected to what is known as the "postmodern condition," critical theory is firmly based on a Marxist view of society putting into question oppresive systems of all levels. As such, it is an activity where interpretation shifts from being passive, consumer-based, and acquiescing, to being active, producer-oriented, and challenging of social, cultural, political, and artistic artefacts (an interesting essay on critical social science along with a review of what critical theory is capable of achieving can be found here).
With the explosion of the "new technologies" and the progressively pervading simulations of reality (-ies), a political consciousness that spans the spectrum of human discourse is not only fascinating but also necessary.