inet6num: 2001,1af0,,/29 netname: HR-ISKON-20040407 country: HR org: ORG-IA28-RIPE admin-c: II385-RIPE tech-c: II385-RIPE status: ALLOCATED-BY-RIR mnt-by: RIPE-NCC-HM-MNT mnt-by: ISKON mnt-routes: ISKON notify: email@example.com created: 2012-11-01T10,32,55Z last-modified: 2017-10-30T08,50,18Z source: RIPE organisation: ORG-IA28-RIPE org-name: ISKON INTERNET d.d. za informatiku i telekomunikacije org-type: LIR address: Garicgradska 18 address: 10000 address: Zagreb address: CROATIA phone: +38516000700 fax-no: +38516000777 e-mail: firstname.lastname@example.org mnt-ref: ISKON mnt-ref: RIPE-NCC-HM-MNT mnt-by: RIPE-NCC-HM-MNT mnt-by: ISKON admin-c: NP1462-RIPE admin-c: II385-RIPE abuse-c: II385-RIPE created: 2004-04-17T11,25,36Z last-modified: 2017-10-30T14,40,50Z source: RIPE role: Iskon Internet address: Garicgradska 18 address: 10000 Zagreb address: Croatia abuse-mailbox: email@example.com e-mail: firstname.lastname@example.org admin-c: NP1462-RIPE tech-c: VZ556-RIPE tech-c: NP1462-RIPE nic-hdl: II385-RIPE mnt-by: ISKON created: 2002-09-05T14,32,38Z last-modified: 2013-01-24T15,36,33Z source: RIPE route6: 2001,1af0,,/29 descr: Iskon Internet d.d. origin: AS13046 mnt-by: ISKON created: 2012-11-13T14,25,11Z last-modified: 2012-11-13T14,25,11Z 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.