inet6num: 2a01,280,1,,/48 netname: SE-RESILANS descr: Resilans AB descr: Servers and backbone. country: SE admin-c: RESI1-RIPE tech-c: RESI1-RIPE status: ASSIGNED mnt-by: RESILANS-MNT created: 2007-01-04T08,19,03Z last-modified: 2008-05-08T12,55,13Z source: RIPE role: Resilans AB address: Resilans AB address: Box 13 054 address: S-103 02 Stockholm address: Sweden phone: +46 8 6881180 e-mail: email@example.com admin-c: WIDL2-RIPE tech-c: WIDL2-RIPE tech-c: GORD1-RIPE tech-c: FISC1-RIPE tech-c: STLP2-RIPE tech-c: ANDR7-RIPE tech-c: NADI4-RIPE nic-hdl: RESI1-RIPE abuse-mailbox: firstname.lastname@example.org mnt-by: RESILANS-MNT created: 2007-12-11T22,46,37Z last-modified: 2014-05-19T11,33,56Z source: RIPE route6: 2a01,280,1,,/48 descr: RESILANS AB remarks: www.resilans.se origin: AS12381 mnt-by: RESILANS-MNT created: 2012-11-14T13,44,31Z last-modified: 2012-11-14T13,44,31Z 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.