The world's first emergency telephone number, 999, is introduced in London.

An emergency telephone number is a number that allows a caller to contact local emergency services for assistance. The emergency number differs from country to country; it is typically a three-digit number so that it can be easily remembered and dialed quickly. Some countries have a different emergency number for each of the different emergency services; these often differ only by the last digit.

999 is an official emergency telephone number in a number of countries which allows the caller to contact emergency services for emergency assistance. Countries and territories using the number include Bahrain, Bangladesh, Botswana, the Cook Islands, Eswatini, Ghana, Guernsey, Hong Kong, the Republic of Ireland, the Isle of Man, Jersey, Kenya, Macau, Malaysia, Mauritius, Niue, Poland, Qatar, Sudan, Saudi Arabia, Singapore, Trinidad and Tobago, Seychelles, Uganda, the United Arab Emirates, the United Kingdom, and Zimbabwe.