inet6num: 2a01,2b0,3009,,/48 netname: Nethousenet descr: Nethouse Sverige country: SE admin-c: NSGS-RIPE tech-c: NSGS-RIPE status: ASSIGNED notify: firstname.lastname@example.org mnt-by: IP-ONLY-MNT created: 2014-08-08T12,25,47Z last-modified: 2014-08-08T12,25,47Z source: RIPE role: Nethouse Sverige Group technical support address: Nethouse Group address: Drottninggatan 2 address: 702 10 Orebro address: Sweden phone: +46 19 164000 admin-c: BA1023-RIPE tech-c: GIS-RIPE tech-c: TS2665-RIPE e-mail: email@example.com nic-hdl: NSGS-RIPE mnt-by: NSG-MNT created: 2004-10-04T09,36,23Z last-modified: 2016-05-20T14,39,46Z source: RIPE route6: 2a01,2b0,,/32 descr: IP-ONLY origin: AS12552 mnt-by: IP-ONLY-MNT created: 2009-02-16T09,55,08Z last-modified: 2009-02-16T09,55,08Z 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.