  Pursuit and evasion conflicts represent challenging problems with important
applications in aerospace and robotics. In pursuit-evasion problems, synthesis
of intelligent actions must consider the adversary's potential strategies.
Differential game theory provides an adequate framework to analyze possible
outcomes of the conflict without assuming particular behaviors by the opponent.
This article presents an organized introduction of pursuit-evasion differential
games with an overview of recent advances in the area. First, a summary of the
seminal work is outlined, highlighting important contributions. Next, more
recent results are described by employing a classification based on the number
of players: one-pursuer-one-evader, N-pursuers-one-evader,
one-pursuer-M-evaders, and N-pursuer-M-evader games. In each scenario, a brief
summary of the literature is presented. Finally, two representative
pursuit-evasion differential games are studied in detail: the two-cutters and
fugitive ship differential game and the active target defense differential
game. These problems provide two important applications and, more importantly,
they give great insight into the realization of cooperation between friendly
agents in order to form a team and defeat the adversary.
