Modern and future colliders

Particle accelerators have been engines of discovery for many decades. The most powerful ones are used in particle physics where intense particle beams collide to study new particles. This has led to groundbreaking discoveries in our understanding of matter and forces. In this article the key concepts behind the development of such colliders are reviewed and a historical perspective is provided of the evolution of these machines. Approaches for next-generation colliders are presented and technology developments for far-future colliders that will have the further benefit of enabling new applications in the use of accelerators for science and society are discussed.