inet6num: 2a00,4802,1a00,,/40 netname: Blizoo-Dobrich country: BG admin-c: RR11927-RIPE tech-c: RR11927-RIPE status: AGGREGATED-BY-LIR assignment-size: 56 mnt-by: AS13124-MNT created: 2017-10-06T12,14,25Z last-modified: 2017-10-06T12,14,25Z source: RIPE person: Rossica Rusenova address: str. Kukush 1 address: 1000, Sofia phone: +359882203597 nic-hdl: RR11927-RIPE mnt-by: AS13124-MNT created: 2017-07-17T06,47,50Z last-modified: 2017-07-17T06,47,50Z source: RIPE route6: 2a00,4802,1a00,,/40 descr: Blizoo Dobrich end customers origin: AS13124 mnt-by: AS13124-MNT created: 2014-05-12T12,52,19Z last-modified: 2014-05-12T12,52,19Z 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.