Go to the internet browser of your choice, and navigate to this link:
Then download and install that program. IzArc is completely free and will never ask you for any personal information. In my personal opinion, IzArc has the easiest interface available and has all the features as WinRar or 7-Zip, and I highly recommend this program to all computer users. After you download you must run the installation program to use it. do this by clicking on the download in your internet browser, or navigating to your downloads directory and running it thrugh there.