The Time Machine, a science fiction novel by H. G. Wells tells the story of the Time Traveller, an English scientist and gentleman inventor living in Richmond, Surrey in Victorian England. The narrator recounts the Traveller's lecture to his weekly dinner guests that time is simply a fourth dimension, and his demonstration of a tabletop model machine for travelling through it. He reveals that he has built a machine capable of carrying a person through time, and returns at dinner the following week to recount a remarkable tale.

The Time Traveller tests his device with a journey that takes him to A.D. 802,701, where he meets the Eloi, a society of small, elegant, childlike adults. They live in small communities within large and futuristic yet slowly deteriorating buildings, doing no work and having a frugivorous diet. His efforts to communicate with them are hampered by their lack of curiosity or discipline, and he speculates that they are a peaceful, common society, the result of humanity conquering nature with technology, and subsequently evolving to adapt to an environment in which strength and intellect are no longer advantageous to survival.

Wells is generally credited with the popularisation of the concept of time travel by using a vehicle that allows an operator to travel purposefully and selectively. The term "time machine", coined by Wells, is now universally used to refer to such a vehicle. This work is an early example of the Dying Earth subgenre.

The story reflects Wells's own socialist political views, his view on life and abundance, and the contemporary angst about industrial relations.

The Time Machine has since been adapted into two feature films of the same name, as well as two television versions, and a large number of comic book adaptations. It has also indirectly inspired many more works of fiction in many media.