This document discusses mobile ad hoc networks (MANETs) and related security challenges. It provides an overview of MANETs, including their evolution, characteristics, and architecture. The document then examines key security issues for MANETs, such as vulnerabilities to different types of attacks, including active attacks like packet dropping, modification, and denial of service attacks. It emphasizes that MANETs require new security solutions due to their lack of infrastructure, dynamic topology, and other distinguishing features compared to traditional wired networks. Overall, the document serves to introduce MANETs and outline important security considerations for further research on this topic.