Today, technological advances (sensors, processors, communication units, etc.), which are rapidly on the road, allow smaller Unmanned Aerial Vehicles (UAV) to achieve the same functions as larger UAVs. To fulfill a given task, the use of multiple UAVs instead of a single UAV has been an area of interest for many years. Also, there are a number of scenarios where a single UAV is inadequate due to a number of constraints (such as airtime, payload and long-distance communication bandwidth etc.). In recent years, the use of multiple UAVs has become possible, especially in the area of avoidance of collision and route finding. Morever, UAVs have become more and more involved in both civilian and military areas, due to the fact that UAV systems have reduced their deployment and maintenance costs and allowed pilots to enter hazardous areas. For example, it is possible to use UAV swarms to overcome complex tasks such as searching for survival signs and multiple target tracking.