2a04:cf40::/29 - DE-SPIRIT21-20140414
inet6num: 2a04:cf40::/29 netname: DE-SPIRIT21-20140414 country: DE org: ORG-SA1493-RIPE admin-c: tk2404 tech-c: tk2404 status: ALLOCATED-BY-RIR mnt-by: RIPE-NCC-HM-MNT mnt-by: S21-MNT mnt-routes: S21-mnt mnt-routes: TXX-MNT notify: email@example.com created: 2014-04-14T11:09:45Z last-modified: 2018-07-05T15:47:28Z source: RIPE organisation: ORG-SA1493-RIPE org-name: SPIRIT/21 AG org-type: LIR address: Otto-Lilienthal-Str. 36 address: 71034 address: Boeblingen address: GERMANY phone: +497031714960 mnt-ref: S21-mnt mnt-ref: RIPE-NCC-HM-MNT mnt-by: RIPE-NCC-HM-MNT mnt-by: S21-MNT e-mail: firstname.lastname@example.org abuse-c: AC28996-RIPE created: 2014-04-11T10:07:46Z last-modified: 2018-07-05T15:47:28Z source: RIPE person: Thorsten Kocher address: Otto-Lilienthal-Str. 36 address: 71034 Boeblingen address: Germany phone: +49 7031 714960 e-mail: email@example.com nic-hdl: tk2404 mnt-by: S21-MNT created: 2014-04-11T15:49:56Z last-modified: 2014-04-11T15:55:16Z source: RIPE route6: 2a04:cf40::/29 descr: Spirit21 via TelemaxX origin: AS12843 mnt-by: TXX-MNT created: 2015-04-28T11:27:05Z last-modified: 2015-04-28T11:27:05Z 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.