How to block a site from your computer

For many reasons we require to

block sites access from our computer

. It is a very simple task and here's how it can be done in windows:
Step 1:
  Go to Start->Run and type the following
     %systemdrive%/windows/system32/drivers/etc
Step 2:
    Open the file with name "hosts" probably in notepad
Step 3:
    Type the following
    127.0.0.1       www.sitetoblock.com


Further details can be found here
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