IPv6 link-local addresses
Link-local IPv6 addresses have a smaller scope as to how far they can travel: only within a subnet that a host is connected to. IPv6-enabled routers will not forward packets destined to a link-local address to other links.
A link-local IPv6 address must be assigned to every network interface on which the IPv6 protocol is enabled. A host can automatically derive its own link local IP address or the address can be manually configured using IOS commands.
Link-local addresses have a prefix of FE80::/10. They are not used for normal IPv6 packet flows that contain data for applications. Instead, these addresses are used by some overhead protocols (such as NDP) and for routing.
Here is a graphical representation of a link local IPv6 address: