The United States Postal Service introduced ZIP codes for US mail.
Source
The UK returned Hong Kong's control back to China after 156 years of British rule.
The Morse code distress signal 'SOS,' originating from Germany, became the world's official message for help.
The US aired its first-ever TV commercial.
The Communist Party of China was founded with Chen Duxiu as the leader.
Sony's iconic Walkman first went on sale in Japan.
