This book briefly describes the basic concepts of Ad-hoc network. the importance of Ad-hoc network and application area are included. The different protocols used in communication is discussed in detail. Some research aspect of these protocols is also included. The merits and demerits of current protocols are analyzed. The improvement strategy is also focused. In final chapter future research trends are also suggested in details. This books can be found suitable for master degree students and research scholars in the domain of Ad-Hoc network.