What's the Hosts fileThe Hosts file is a computer file that is used by the operating system to map hostnames to IP addresses. The hosts file is one of several system facilities that assists in addressing network nodes in a computer network. It is a common part of an operating system's IP implementation, and serves the function of translating human-friendly hostnames into numeric protocol addresses, called IP addresses, that identify and locate a host in an IP network.
The Hosts file contains lines of text consisting of an IP address in the first text field followed by one or more host names. Each field is separated by white space (Tabs are often preferred for historical reasons, but spaces are also used). Comment lines may be included, and they are indicated by a hash character (#) in the first position of such lines. Entirely blank lines in the file are ignored.