People have been sending letters to each other ever since paper and pen were invented, but it was not until 1840 that a new idea was introduced where people could prepay the cost of delivering their letter to their chosen destination using a Penny Black postage stamp. This was the Universal Penny Post. No longer did the recipient have to give money to the person who delivered the letter or pay a wildly differing amount depending on how far and how long the letter had travelled. The post system became highly efficient, and at one penny a stamp, it was a service just about anyone could afford.
This is a companion discussion topic for the original content at https://www.worldhistory.org/Penny_Black/.