inet6num: 2406:a400::/32 netname: LGA-SG descr: LGA International country: SG org: ORG-LI3-AP admin-c: AA48-AP tech-c: TC113-AP mnt-lower: MAINT-SG-LGA mnt-by: APNIC-HM status: ALLOCATED PORTABLE mnt-irt: IRT-LGA-SG last-modified: 2017-08-29T23:08:14Z 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.