An important note before we begin -- a warning that you should already be aware of. You should not download any data from the internet without some up-to-date virus protection running on your computer. If you do not already have virus protection there are several free products available, including AVG Anti-Virus for windows and Avast! antivirus, which is available for windows and linux. You can also purchase antivirus software such as Norton Antivirus or McAfee VirusScan® Plus.