inet6num: 2001:df5:3200::/48 netname: IDNIC-LAPAN-ID descr: Lembaga Penerbangan dan Antariksa Nasional (LAPAN) descr: Government / Direct Member IDNIC descr: Gedung LAPAN Pusat descr: Jl. Pemuda Persil No.1 descr: Jakarta Timur 13220 admin-c: SSA26-AP tech-c: SSA26-AP remarks: Send Spam & Abuse Report to: email@example.com country: ID mnt-by: MNT-APJII-ID mnt-irt: IRT-LAPAN-ID mnt-routes: MAINT-ID-LAPAN status: ASSIGNED PORTABLE last-modified: 2018-01-11T08:03:53Z source: APNIC
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.