# Global Unicast Addresses

**Global unicast** IPv6 addresses are public addresses that can be used over the Internet

Must register to use them. Because they are public addresses, it is expected that they are globally unique.

Originally defined as the 2000::/3 block (2000:: to 3FFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF:FFFF).

Now defined as all addresses which aren't reserved for other purposes.

<figure><img src="https://1474932522-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FAgItg4KAZpnXjAFPWRf8%2Fuploads%2FGBXmQ855QgxjOGrZqfIn%2FScreenshot%20from%202023-07-15%2018-17-55.png?alt=media&#x26;token=2c249e76-af0c-48ff-8a27-3da691d9aedd" alt=""><figcaption></figcaption></figure>
