Celebrate Bisexuality Day is observed worldwide on September 23, 2018 by members of the bisexual community and their supporters. The day, which is celebrated annually, is a call for the bisexual community, their friends and supporters to recognize and celebrate bisexuality, bisexual history, bisexual community and culture, and the bi- and pansexual people in their lives.
First observed in 1999, Celebrate Bisexuality Day is the brainchild of three United States bisexual rights activists: Wendy Curry, Michael Page, and Gigi Raven Wilbur. This celebration of bisexuality in particular, as opposed to general LGBT events, was conceived as a response to the prejudice and marginalization of the bisexual persons by some in both the straight and greater LGBT communities.
Bisexuality is sexual behavior or an orientation involving physical or romantic attraction to males and females, especially with regard to men and women. It is one of the three main classifications of sexual orientation, along with a heterosexual and a homosexual orientation, all a part of the heterosexual–homosexual continuum. (With material from: Wikipedia)