Explanation

World Telecommunication and Information Society Day (WTISD) is celebrated annually on May 17.

The date was chosen to commemorate the founding of the International Telecommunication Union (ITU) on May 17, 1865, marking the day the first International Telegraph Convention was signed in Paris.

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Explanation

International Tea Day is celebrated on 21 May annually 

First time celebrated in 2020 by the United Nations.  

Theme 2025: Tea for Better Lives

Theme 2026: Sustaining Tea, Supporting Communities

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Explanation

World Hypertension Day is observed annually on May 17 to raise global awareness about high blood pressure.

Since 2006, the WHL has been dedicating May 17 of every year as WHD.

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Explanation

World Metrology Day is celebrated annually on May 20 to commemorate the signing of the Metre Convention in 1875.

2026 Theme: "Metrology: Building Trust in Policy Making".

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Explanation

World Turtle Day is an annual observance held every May 23rd.

It began in 2000 and is sponsored by American Tortoise Rescue.

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