This course is an introduction to the fundamentals of game theory. While originally developed to model socio-economic phenomena, Game Theory has recently emerged as a powerful framework to efficiently solve optimisation and multi-agent decision problems in engineering and computer science. After presenting the basic concepts from the theory of strategic form games, the course will focus on learning dynamics and their convergence properties. Particular emphasis will be placed on the study of network games, intervention and mechanism design problems, and more generally on applications of game theory to socio-technical network systems.