Today's lecture is about the history of the bicycle. The first pedal-powered bicycle was invented in the 1830s by a Scottish blacksmith named Kirkpatrick MacMillan. However, it wasn't until the 1880s that the 'safety bicycle' with two equal-sized wheels became popular, making cycling accessible to a wider audience, especially women. The lecturer also mentions that the introduction of pneumatic tires in 1888 by John Boyd Dunlop greatly improved comfort, but the key point is that the safety bicycle's design was crucial for mass adoption.