What is the different between a resistance movement and a terror organization?
A terror organisation, as its name implies, wants to cause terror in the population at large in order to achieve its political ends. It therefore attacks at random, and attacks civilian targets that many people use (aircraft, public buildings), to make them nervous about places they have to go in their normal life. A resistance movement wants to get rid of an occupying power, and therefore attacks only that occupying power, its troops, and the facilities they use. So far as is reasonably possible, a resistance movement tries not to harm people (often the people they are trying to free) carrying on with their normal lives.