There are at two dates to celebateWorld Book Day. Hashtag: #WorldBookDay
The official event hosted by United Nations Educational, Scientific and Cultural Organization (UNESCO) is April 23 as World Book Day was first celebrated on April 23, 1995. This celebration is also known as World Book and Copyright Day, or International Day of the Book and celebrates promote reading, publishing, and copyright.
In the UK World Book Day is March 7.
World Book Day