The operating principle of dielectric elastomer (DE) is based on Maxwell stress generated by electric (static) fields which results in squeezing of the dielectric film and therefore in large deformation of the entire composed structure. Since the dielectric elastomer film squeezes in thickness direction and expands in planar direction at applied electrostatic field two different basic actuation modes of the DE structure can be achieved as they are the expanding or contracting deformation. In this presentation the "expanding" actuator based on the membrane design as well as the "contractive" active structure composed of many layers in stack design are reviewed with special focus on both actuation modes under external loads. Additionally some challenging technological aspects are discussed concerning manufacturing process and design parameters.