Context is the challenge for the coming years in artificial intelligence. In the companion paper [8], we present the main results of discussions at two workshops and at the first conference focusing on the notion of context. In this paper, we present a view of how context is considered in knowledge acquisition, machine learning, communication, and databases and ontologies. We describe the way in which context is modelled and represented in the logic formalism and a rule-based formalism. We present briefly after some of the other approaches, and sum up the different points that may be of interest for modelling context effectively.