Blocking a website with host files.?

I've gotten to my host files program, and out of all the tutorials, I notice something weird about my host file.

Here is the file:

# Copyright (c) 1993-2006 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

::1 localhost

Now I know normally at the bottom it says 127.0.0.1 localhost, but mine has the ::1 localhost. I was wondering what I should do next since mine is different?