This article aims to provide a panorama of the fundamentals related to Agents. Specifically, the most popular definitions behind the concept of Intelligent Agents and the main properties that characterize an agent are discussed along with different agent-based models. Furthermore, the concept of Environment as well as its properties and the role that it plays in the context of the agent paradigm are presented. Actions and Interactions among agents and environment are also discussed before contextualizing the role of Intelligent Agents in the Computational Biology domain.