Meh I mean I’m a sense they you’re passing messages between different servers on different domains using similar protocols, with similar account notation, yeah. It works as a high level intro.
Not in the sense of the user experience, but in how it actually works.
People get their email from different places (gmail, yahoo, hotmail, outlook.com, their work, whatever) and they all use the same format and protocol and send email from one site to another over the great big internet and no matter where you get your email from it will work with everyone else.
Now, Usenet is honestly a much better analogy, but nobody knows what that is anymore.
It's not that complicated, if you know the person you are trying to teach you could just appropriate a short analogy.
For example if I was talking to a CSGO player I would just tell them Reddit, Twitter, etc are just plain AK47s while the fediverse is a M4A4 that you get to choose a skin for (the site that you sign up to access the fediverse).
Imagine if there's a club where people dance. It's great fun, but the club is owned by a single person. That person has the final say in all decisions: what dances are allowed, which clothes are acceptable to wear, which food you can bring, etc.
This is often good: it is an easy way to avoid people bringing stinky food to the club, ruining the experience for many others, or people dancing in a way which might make others uncomfortable.
However, that person (and the person helping them, either employees or moderators) is in turn also able to make decisions which aren't very popular, like suddenly requiring an ID check to get into the club.
Some people who wanted their dancing not be directed by person disconnected from their life then went ahead and made their own club. But the question was: how can they avoid that they become like the jackass who wants to dictate how people dance?
The answer: federation. People can use their membership in those new clubs at other federated clubs, enabling them to freely check out other clubs without any hassle.
The customization and community aspect is a nice side-effect: there are now clubs focused on e.g. classic dances, who might go for a more classical design of their dance halls or have a certain dress code.
Plain food => food but you get to choose (which) spice(s)
Plain dancing => dancing but you can choose which clothes to wear while dancing
Plain grammar => talking but you can choose a dialect and or accent
Plain cat => you can choose which cat you like from an animal shelter
Though they all fundamentally revolve around platforms that enable sharing content, the main difference usually is, at least to me personally, the interface through which you access the content.
Can't think of (good) analogies for lawsuits, sadly don't know enough about nail polish, and it's too late into the night for me to think about biology.
It's also too late for me to see if what I said made sense or is plain bullshit
My explanation is always that it's like email. Everyone's familiar with email to some extent. You can send an email to anyone from an address anywhere. All they need to do is implement the same protocal.