If you're a POC you'll probably understand this better because I know in Asian cultures light skin vs dark skin is pretty big; but if not, here's a look into the black colorist divide.
What is light skin and dark skin?
I'm going to assume you can use reasoning to figure it out but obviously light skins are light skinned black people and dark skins are dark skinned black people.
I know many people get confused as to what qualifies as light skin and what qualifies as dark skin.
This shade and above is typically considered dark skin:
How did this get started?
So I could give a whole history lesson dating back to ancient Egypt and colonial powers invading Africa but that's too long and I have too few time. so put into a brief over time and history light skin people where typically nobility and dark skinned people were slaves and pesants (or during American slave trade house slave vs field slave). So at the very least skin color shows status.
This really started to take off, in America at least, during the 30's, through something called milatos. Milato is a person whose mixed between black and white. But has later meant to represent a lightskin black person. Milatos were people who had light skin and striaghter hair and would pass as white. They could walk around a lot of the racial descrimination happening at the time, so light skin became the cheat code to an easier life that everyone wanted.
How it's integrated into modern culture
So now with how it's incorporated into modern culture; with social network only amplifying all of the worlds problems and bringing them to the public eye. I'm not sure who started it or how but it's belived to have all started with #lightskin. Socially light skins are very proud to admit to being a light skin once again it's a status symbol. So page after page of selfies began to be tagged with the #teamlightskin and dark skins finally sticking up decided to fight back with their own team.
The best way to explain it is hair color
If you still don't understand, a light skin is the equavalent to white people's blonde. They are seen as less smart but their attractiveness makes up for it. They are also considered prettier. And dark skins are like brunettes; less attractive but considered more intelligent because they have to rely on their wits.
So...What is the point?
Just like blondes vs brunettes there really is no point. It's honestly bullshit we made to continue making peers and further seperation. I truly think the black community relies on other people's stadards of our own beauty, for validation. I think the only real way to get past it is to realise it doesn't really matter. Others have their own idea of how we look but we just need to choose to not to pay attention to them. Hopefully we can be the first group to understand that the diversity in us is what makes us so unique and beautiful.
The point of this isn't to make anyone feel bad...
So if you think this was an attack on light skin or white people, it geuinly isn't. I'm not blaming anyone because the whole thing is dumb. It's just to shed light on this because I've been asked about it many times.