Viruses are capable of infecting any type of code and program files in your computer. In your disks or system areas of your hard drive, viruses infect what is called “executable” code, which is the software language that tells your computer’s hardware what to do. You need to look out for macro viruses that spread through word processing or spreadsheet documents using macros. JavaScript, .exe program files or Word .doc files, which your computer will actually try to execute, are problem areas for computer viruses or malware. The good news is that many files are safe because they contain only pure data such as text, graphics and sound. Just viewing or listening to gif, .jpg, .mp3 or .wav files won’t release a virus into your computer.