Web 3 is just the decentralized web. It is a possible future, which we are not even there yet. Our mainly applications today are all based in social media and high use of personal data , which is the web 2.0
A web 4 or 5 will eventually happen, after some disruptive technology shows up. It will take some years for sure.
I recently made a summary about web 1 2 and 3:
A brief history of the web:
Web 1.0:
Static webpages, such as geocities. From 1990 to 2004.
That web phase is also known as "read only web"
Web 2.0
Since 2004 until today (yeah, we are on web 2)
Read-write web.
It growed with social media platforms where everyone can share content and read and write on the web. Main name is Facebook.
There is a great problem with centralization and ownership of personal data
Web 3
Is related to decentralized app, and ia still in development. Ethereum and bitcoin are the main names.
Read-write-own
More details here:
https://ethereum.org/en/web3/
