inet6num: 2a02,13a0,,/32 netname: UK-FASTNET-20100519 country: GB org: ORG-FIL1-RIPE admin-c: JP9637-RIPE tech-c: JP9637-RIPE status: ALLOCATED-BY-RIR mnt-by: RIPE-NCC-HM-MNT mnt-by: FN-RIPE mnt-routes: FN-RIPE notify: firstname.lastname@example.org created: 2010-05-19T15,08,28Z last-modified: 2017-11-06T12,38,26Z source: RIPE organisation: ORG-FIL1-RIPE org-name: FastNet International Ltd org-type: LIR address: Shaftesbury Court, 95 Ditchling Road address: BN1 4ST address: Brighton address: United Kingdom phone: +44 1273 662888 fax-no: +44 1273 621631 e-mail: email@example.com abuse-c: AR17647-RIPE mnt-ref: FN-RIPE mnt-ref: RIPE-NCC-HM-MNT mnt-by: RIPE-NCC-HM-MNT mnt-by: FN-RIPE admin-c: NP1213-RIPE admin-c: JP9637-RIPE created: 2004-04-17T12,14,37Z last-modified: 2017-11-06T12,38,27Z source: RIPE person: James Parker address: Fastnet International address: Shaftesbury Court address: 95, Ditchling Road address: Brighton address: BN1 4ST address: England phone: +44 1273 688088 fax-no: +44 1273 621631 e-mail: firstname.lastname@example.org nic-hdl: JP9637-RIPE notify: email@example.com mnt-by: FN-RIPE remarks: remarks: # Please send all abuse reports to firstname.lastname@example.org remarks: created: 1970-01-01T00,00,00Z last-modified: 2013-08-22T09,11,08Z source: RIPE route6: 2a02,13a0,,/32 descr: IPv6 Routing for Fastnet International origin: AS12519 mnt-by: FN-RIPE created: 2012-11-19T16,49,15Z last-modified: 2012-11-19T16,49,15Z source: RIPE
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.