A windows hosts file should look like this:
code:
# Copyright 
1993-1999 Microsoft Corp.
#
# This is a sample HOSTS file used by Microsoft TCP/IP for Windows.
#
# This file contains the mappings of IP addresses to host names. Each
# entry should be kept on an individual line. The IP address should
# be placed in the first column followed by the corresponding host name.
# The IP address and the host name should be separated by at least one
# space.
#
# Additionally, comments (such as these) may be inserted on individual
# lines or following the machine name denoted by a '#' symbol.
#
# For example:
#
# 102.54.94.97 rhino.acme.com # source server
# 38.25.63.10 x.acme.com # x client host
127.0.0.1 localhost
127.0.0.1 google.com
The last line is one which I added as an example. With that there, programs will think that the IP address for google.com is 127.0.0.1 (which is always your your own computer. When I try to load
http://google.com/, the browser will try to contact a server on my own computer, and since there isn't one, will return an error that the server couldn't be contacted. Instead of 127.0.0.1 there could be another IP address.
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