International Gin and Tonic Day is observed worldwide every October 19, celebrating the iconic cocktail made from gin and tonic water. The holiday honors Mary Edith Keyburn, who passed away on this date in 2010 with a gin and tonic at her bedside, a testament to her love for the drink. The gin and tonic originated in the early 19th century as a remedy for malaria, where British officers mixed quinine with gin, lime, and sugar to mask the bitter taste. Although not listed among official cocktails by the International Bartenders Association due to its simplicity, it remains a classic drink. People celebrate by enjoying gin and tonics at bars or making them at home, often garnished with lime or various other ingredients like cucumber or mint. Participants are encouraged to share their drinks on social media using hashtags to promote the holiday.