September 16th-23rd is Bisexual Awareness Week, culminating in Bisexual Awareness Day on Saturday the 23rd. This is a week to celebrate the bisexual community, cultivate acceptance, and bring awareness to the experiences and challenges of bi people. Bi Week was originally founded by GLAAD and BiNet USA in 2014 and is currently co-led by GLAAD, Still Bisexual, and the Bisexual Resource Center. If you decide to make any posts on social media this week, their official tag is #BiWeek!
The bisexual pride flag was designed in 1998 by Michael Page. He stated that the colors pink, purple, and blue were inspired by Liz Nania's biangles, or bisexuality triangles, created in 1985. The pink and blue are described by some sources to represent traditional notions of masculinity and femininity, while others categorize pink as a symbol for homosexuality and blue for heterosexuality.
The purple represents queerness, referencing the 1970s Lavender Menace and other queer organizations that used lavender as a symbolic queer color. The triangles themselves are a reference to the pink upside down triangle used by nazis to identify gay men in the 1930s and '40s. The pink triangle later became a symbol of queer resistance in the 1980s. For more information on the history of the bi flag and its symbolism, this article from Time Magazine is pretty cool!