The first ‘airmail’ was used by the Egyptians through pigeons in 2500 BC. Pigeons were used widely throughout the world. One may be surprised to know that the Orissa (now Odisha) Police used to have a wing of training pigeons to send letters and communications to its units in the state till some 15 years ago.
The pigeon mail was used by the Germans in German-French war in 1870-71. Later they began to use hot air balloons for the purpose. But by 1940, planes began to be used for carrying letters across cities, countries and continents. Now that the email and phones have become too common, airmail is used only for sending documents, books and gifts. Letters are mainly exchanged through emails