inet6num: 2406:9600::/32 netname: IPv6-THENET-ID descr: PT. Millenium Internetindo descr: Internet Service Provider descr: Jakarta country: ID admin-c: TA1-ID tech-c: TH2-ID status: ALLOCATED PORTABLE remarks: Send Spam& Abuse report to firstname.lastname@example.org mnt-by: MNT-APJII-ID mnt-lower: MAINT-THENET-ID mnt-routes: MAINT-THENET-ID mnt-irt: IRT-IDNIC-ID last-modified: 2011-01-30T22:53:50Z source: APNIC
IP address ranges, or netblocks, are groups of related IP addresses. They are usually represented as a base IP address, followed by a slash, and then a netmask which represents how many IP addresses are contained within the netblock. This format is known as CIDR. You'll also sometimes see netblocks given as a start ip address, and an end ip address, or an ip address range.
Traffic works its way around the internet based on the routing table, which contains a list of networks and their associated netblocks.