the.com/hostname
the nickname your computer tells other computers so numbers don't have to.
means a human-readable label assigned to a device on a network, standing in for its numeric address.
from from arpanet's 1970s hosts.txt file, a single master list mapping names to addresses for every machine online, later obsoleted by dns when the internet outgrew one spreadsheet.
max length253 characters total, 63 per label
case ruletechnically case-insensitive, unlike almost everything else
localhostalways resolves to your own machine, no network needed
charset limitonly letters, digits, and hyphens allowed
for instance
localhost — universal loopback name, resolves to 127.0.0.1 everywhere