inet6num: 2a00,1288,,/32 netname: UK-YAHOO-20090819 country: GB org: ORG-YE1-RIPE admin-c: YEU-RIPE tech-c: YEU-RIPE status: ALLOCATED-BY-RIR mnt-by: RIPE-NCC-HM-MNT mnt-by: YAHOO-MNT mnt-routes: YAHOO-MNT notify: firstname.lastname@example.org mnt-domains: YAHOO-MNT created: 2009-08-19T11,51,13Z last-modified: 2017-08-03T17,11,53Z source: RIPE organisation: ORG-YE1-RIPE org-name: Yahoo! UK Services Limited org-type: LIR address: 125 Shaftesbury Avenue address: WC2H 8AD address: London address: UNITED KINGDOM phone: +442071311495 fax-no: +14083497102 tech-c: LV3435-RIPE mnt-ref: YAHOO-MNT mnt-ref: RIPE-NCC-HM-MNT mnt-by: RIPE-NCC-HM-MNT mnt-by: YAHOO-MNT admin-c: NA1231-RIPE admin-c: IG1154-RIPE admin-c: LV3435-RIPE abuse-c: NA4112-RIPE created: 2004-04-17T12,24,22Z last-modified: 2017-08-03T17,11,55Z source: RIPE e-mail: email@example.com role: Yahoo Europe Operations Department address: Yahoo Europe Operations address: 125 Shaftesbury Avenue address: London address: WC2H 8AD remarks: trouble, firstname.lastname@example.org e-mail: email@example.com admin-c: NA1231-RIPE tech-c: NA1231-RIPE tech-c: IG1154-RIPE nic-hdl: YEU-RIPE mnt-by: YAHOO-MNT created: 2005-02-21T10,54,13Z last-modified: 2014-03-25T20,11,11Z source: RIPE abuse-mailbox: firstname.lastname@example.org
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.