Today we're going to discuss the history of the bicycle. One key figure was Karl von Drais, who invented the 'running machine' in 1817. This early model had no pedals; riders pushed their feet against the ground. Later, in the 1860s, pedals were added to the front wheel, leading to the high-wheeled 'penny-farthing'. However, these were dangerous due to their height. It wasn't until the late 1880s that the 'safety bicycle' with a chain drive and equal-sized wheels became popular, making cycling accessible to a wider range of people.