Today's lecture is about the history of the bicycle. The first bicycle, invented in the early 19th century, had no pedals and was pushed along by the rider's feet. This design was called a 'hobby horse.' Later, in the 1860s, pedals were added to the front wheel, creating the 'velocipede.' However, it was not until the 1880s that the 'safety bicycle' with two equal-sized wheels and a chain drive became popular. This design made cycling much safer and more comfortable, leading to a bicycle boom in the 1890s. Interestingly, the safety bicycle also played a role in women's liberation, as it gave women greater mobility and freedom.