I will explain with an analogy on how to think and learn nostrl.

Think of nostrl as a medium of travelling. It could be roadways, railways or airways. Likewise nostrl. It is a way or medium of travelling. Now when you are travelling, the vehicle you are travelling on will be your client. Like buses, cars to travel on nostrl you need a client.

The most famous ones are:

And so on. There are many vehicles/clients that you can use to travel. Just remember it doesn’t matter what vehicle/client you use, you are still on nostrl. Nostrl is the medium, clients are the vehicles to travel on this medium.

Think of it as your ticket of the journey ; Public key your name on the ticket is your public name, through which people will recognise you. Private key is your password to access your ticket. Remember not to share your private key to anyone, sharing your key and people will steal your ticket:)