Good morning, everyone. Today we're going to talk about the history of the bicycle. Now, many people think the bicycle was invented in the 19th century, but in fact, the first two-wheeled vehicle appeared in 1817, invented by a German baron named Karl von Drais. However, this early model, called the 'draisine', had no pedals; riders pushed their feet against the ground to move. It wasn't until 1860s that pedals were added to the front wheel in France. Interestingly, the modern chain-driven bicycle with two equal-sized wheels was developed in England in the 1880s, which made riding much safer and more efficient. So, to sum up, the key development that made bicycles popular for everyday use was the introduction of the chain drive.