This document discusses constructivism and social constructivism as learning theories and how computers can support these paradigms. Constructivism posits that learners build knowledge through personal discovery, while social constructivism emphasizes that social and cultural contexts influence knowledge construction. The computer can function as an information tool by providing vast resources, as a constructive tool by allowing learners to manipulate and organize ideas, as a co-constructive tool by facilitating collaborative knowledge-building, and as a situating tool by immersing learners in virtual environments.