inet6num: 2001:4100::/32 netname: AT-PSC-20040908 descr: PROVIDER Local Registry country: AT org: ORG-iG1-RIPE admin-c: AP2344-RIPE tech-c: AP2344-RIPE status: ALLOCATED-BY-RIR mnt-by: RIPE-NCC-HM-MNT mnt-by: INTERNIC-MNT mnt-routes: INTERNIC-MNT notify: firstname.lastname@example.org notify: email@example.com created: 2004-09-08T08:39:36Z last-modified: 2018-06-05T10:55:28Z source: RIPE organisation: ORG-iG1-RIPE org-name: internic Datenkommunikations GmbH org-type: LIR descr: Abuse reports to: firstname.lastname@example.org address: Schoenngasse 15 - 17 / 8 address: 1020 address: Wien address: AUSTRIA phone: +43 1 3249685 fax-no: +43 1 3249686 e-mail: email@example.com abuse-c: AR14101-RIPE admin-c: AP2344-RIPE mnt-ref: INTERNIC-MNT mnt-ref: RIPE-NCC-HM-MNT notify: firstname.lastname@example.org mnt-by: RIPE-NCC-HM-MNT mnt-by: INTERNIC-MNT created: 2004-04-17T10:59:24Z last-modified: 2018-06-05T10:57:36Z source: RIPE person: Andreas Paumann address: internic Datenkommunikations GmbH. address: Puchsbaumplatz 2 / 7-8 address: A-1100 Wien address: Austria phone: +43.1.3249685 fax-no: +43.1.3249686 e-mail: email@example.com nic-hdl: AP2344-RIPE notify: firstname.lastname@example.org mnt-by: INTERNIC-MNT created: 1970-01-01T00:00:00Z last-modified: 2018-06-07T07:34:05Z source: RIPE route6: 2001:4100::/32 descr: AT-INTERNIC-2001-4100 descr: internic GmbH., Vienna origin: AS12401 mnt-by: INTERNIC-MNT created: 2011-02-10T15:23:26Z last-modified: 2011-02-10T15:23:26Z 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.