You’ve heard of bitcoin. Its built using the blockchain. This is a distributed database that keeps track of every bitcoin transaction. Bitcoin popularity may have diminished, but the importance of the blockchain as truly revolutionary technology remains.
The Internet’s key design objective was to survive nuclear attack. The need for resilience is what led to the distributed design pattern. But certain core features, like the IP address space and Domain Name Servers (DNS) systems were never decentralised as the solutions had yet to be defined.
Even early peer-to-peer products (like Skype and Napster) relied on managed super-nodes or centralised directories.
The blockchain provides a method of distributing trust and facilitating decentralised systems.
This excellent IEEE Spectrum essay explores how the blockchain could inveigle its way to improving core internet services from payment transactions, to online communities, to video games, to preventing spam email and more.