The concept behind Nostr is to create a decentralized and censorship resistant social network. In fact, on Nostr there is no content censorship, there is no body that decides what can be published and what cannot. It can be very useful for spreading information (but also fake news) without an entity being able to censor it (such as Twitter, Facebook, Youtube) but also for implementing a payment system (which you can already use with Bitcoin anyway).
There is no need to give emails, mobile numbers and personal data. This social network is based on encryption and digital signatures and uses a client useful for creating a pair of keys: one public and one private. To publish a post (note) I have to sign it with a private key, it is then sent to a relay (they are type servers made available by volunteers) which receives it, saves it to disk and shares it. Clients also verify that each note has not been compromised and has been signed correctly, which prevents the data from being tampered with. The various relays put all the users (clients) in communication by sharing the notes published by other users. The contents are validated by the relays which theoretically should share them without censoring them. Anyone can create a relay and still share that information. The big problem is that, as of today, there are no financial incentives to keep a relay running so some may go offline (content may disappear and reappear later).
CLIENTS TO USE
There is no centralized web server/domain. It is possible to use Nostr with many web clients. You then easily create many identities (just like I can create multiple wallet addresses). The infrastructure consists of:
1) clients (they are like wallets that sign and send notes)
2) relay (entities that receive data and share it, the data is encrypted end to end and cannot be accessed)
3) users of course (accounts with private/public key)
Among the best known clients we find Snort (computer and Android), by logging in I can generate a private key online by pressing on "generate key" or I can generate it using the Nos2x Chrome extension (this is the safest thing). The private key, once generated, must be saved (otherwise you will lose access to your page forever). It represents your digital identity on Nostr. If I used the extension, from Snort I can log in with this extension and authorize the connection for a variable time (5 minutes, just for now, forever). This is the registration to this network.
Then I can update the profile by writing name, nick, biography, profile picture, etc
I can also enter a Lightning Network address (Wallet Of Satoshi for example, here you will find a list of Lightning Addresses, I will enter the email address associated with my LN wallet) to receive "tips" (basically what happens with Brave Browser or Publish0x), i.e. of payments.
Another client is Astral Ninja from which I can always log in with the same extension or generate another digital identity and therefore a private key. If I use the same extension, my data entered on Snort will also be found here because the identity (private/public key) is the same. Through this web client it is easier to search for profiles to follow.
Other clients: Amethyst (Android), Damus (iPhone) and Iris (web). You must bear in mind that a private key works in a similar way to that of non-custodial wallets. Through this private key I can log in on any client that supports this model: the profile and the contents are saved on this decentralized network. Obviously you have to be careful where you insert the private key because if it is stolen you cannot change it!
I think it's an interesting experiment. Imagine if you could use a single client that saves all your posts for all the social networks you use. A private key that entered on Twitter, Facebook, Instagram, makes all your messages appear regardless of the social network you are using. This example is very forced because in this case we are dealing with centralized social networks with their own website, but it is to give you an idea. With Nostr you can use dozens of different web clients and with their interface but the contents are saved on your private key and shared by the relays.
The utility is evident, however, there are many aspects to improve. Without financial incentives, relays may not always stay online. When a relay is not online, some posts or followers may temporarily disappear. The biggest challenge, however, remains adoption. The system of using private keys makes the social network not very usable by the masses. I am referring to those who have no mastery of non-custodial wallets.
However it is a very interesting case study.
OTHER CRYPTO SOCIALS
Something similar had already been done by Deso (Decentralized Social). Always connected to the Crypto world but not decentralized social as it is based on login credentials, we find the Torum social network which also allows you to earn the platform's native token by posting content and carrying out some operations.
Are you interested in ways to earn crypto bonus? Check it out here: Some Sites To Earn Crypto Bonus (Old & New)