Communications have always been, and are still a vital part of the Army's fighting power. Only with clear and trusted communications can commanders support, control, and lead their units and soldiers. The evolution of electrical communications in the last 150 years has been one of the most important developments humanity has ever witnessed. As the advantages that from ever more complex equipment became apparent the need for a technical arm of the Army, who specialised in communication systems, became apparent. The Royal Corps of Signals was founded in 1920 and since its founding the Corps has been leading the development of communications; delivering them in a variety of operational theatres.