RFC 2460 is a document that specifies the format and structure of IPv6 packets, which are used for internet communication. It was published in December 1998 and serves as a foundational standard for the next generation of internet protocol, addressing the limitations of IPv4. The document outlines how IPv6 addresses are structured, how packets are processed, and the requirements for routers and hosts. It aims to ensure efficient data transmission and improve the overall functionality of the internet as more devices connect globally.