World Quality Day is one of the international observances, that annually falls on the second Thursday in November. This observance was introduced by the United Nations in 1990, but it didn't become one of the UN special international days.
World Usability Day is annually celebrated on the second Thursday in November. It was created to promote the values of usability and user's responsibility to ask for things that work better.
World Science Day for Peace and Development is a United Nations observance held on November 10. It was officially proclaimed by the UNESCO General Conference in 2001. This event focuses on demonstrating to the wider public why science is relevant for their daily lives.