#ChallengeAccepted: why black and white photos are flooding social media

Over the past few days, social media has been flooded with black and white photos as women share snaps of themselves with the caption "Challenge Accepted", perhaps an empowering message to other women, and nominations for others to do the same.

"Truth be told, I don’t really understand this #ChallengeAccepted thing, but who doesn't love a good reason to support women," actress Jennifer Aniston admitted as she joined the trend on Instagram.

If, like Aniston, you've spotted these posts but aren't sure what they're all about, here's what you need to know:

WHAT IS THE CHALLENGE?

The challenge is about "spreading positivity" by posting a black and white photo of yourself using the #ChallengeAccepted and #WomenSupportingWomen hashtags — and to keep the chain going by nominating other women to do the same.

Many people are adding words of encouragement for other women, or an inspirational quote about women.

A spokesperson for Instagram told the The Independent the trend is all about women showing support for each other, and is meant to "celebrate strength, spread love and remind all women that supporting each other is everything".

WHERE AND WHY DID IT START?

While the origins of the current #ChallengeAccepted hashtag remain unclear, an expert told the New York Times the trend may have been sparked by a video of US politician Alexandria Ocasio-Cortez recently confronting sexist remarks made against her.

WHO HAS JOINED IN?

The #ChallengeAccepted hashtag has garnered more than three-million posts on Instagram and topped the trends list on Twitter. Beyond ordinary women — and a few men — many celebs have embraced the trend.

International A-listers who've jumped on the bandwagon include Reese Witherspoon, Gabrielle Union, Jennifer Lopez and Halle Berry, while local stars including Basetsana Kumalo, Minnie Dlamini-Jones, Boity and Unathi Nkayi have taken part.

Here are some of their posts: