Pictured are some human powered devices;
a push along lawnmower, a bicycle (with dynamo front light) a wind-up alarm clock, a wind up pocket watch, a wind up radio, and a wind up torch.
The bicycle light is powered by the dynamo which generates electricity only when the front wheel is turning, no energy is stored.
In the alarm clock and the pocket watch energy is stored in a spring which, as it unwinds, powers the mechanism.
In the wind up radio energy is also stored in a spring, which drives a dynamo to power the radio.
In the wind up torch energy is stored in a rechargable battery which is charged by a dynamo when the handle is turned.