Okay, so let's imagine a really big playground with lots and lots of kids. Some kids might play on the swings, some might play on the jungle gym, and others might play a game of tag. But even though they all play different games, they all have something in common - they're all on the playground together.
Now let's imagine that each group of kids playing a different game makes their own rules and doesn't really pay attention to what the other groups are doing. This is kind of like what a segmentary society is.
In real life, a segmentary society is a group of people who live near each other but don't really work together as a big group. Instead, they might have different clans or families that each have their own rules and ways of doing things. These clans might compete with each other for resources like land or water, even though they're all living in the same area.
Just like the kids on the playground, people in a segmentary society might not really pay attention to what the other groups are doing. They might cooperate with their own group, but not with others. This can sometimes lead to conflict if different groups' needs and rules clash with each other.
So, a segmentary society is kind of like a big playground where each group has their own rules and they don't really work together as one big group.