Today we're going to discuss the history of the postal service. In the early 19th century, mail was delivered by horseback riders, which was slow and unreliable. Then, in 1840, Britain introduced the penny post, which standardized the cost of sending a letter regardless of distance. This made mail affordable for ordinary people. Later, in the late 19th century, the invention of the railway and steamships greatly sped up international delivery. However, it wasn't until the 20th century that airmail became common, especially after World War II. So, the key turning point for public access was the penny post, not the later technological advances.