However since Winzip and StuffIt are the most popular, we will assume you will use either one to compress and decompress your own files. If you download a compressed file from a website or file library that ends in an .exe extension, take note that although the file is compressed, it's typically a file that will install a program onto a computer. For instance, let's say that Program A is already installed on a computer and it's working just fine. Then let's say that the user of that computer downloads and installs Program B. Program B uses a file that Program A installed much earlier, but when Program B is run, errors popup. Those errors are the result of Program B attempting to use an outdated (shared) file that was installed by Program A. Smartphones have been all over the news and chances are, you do know what they are - only you know them under a different name. Smartphones are mobile phones with computer like capabilities. What's that? Aha! Yes, you've not only heard of them, you've probably seen them as well. Packed with Internet access, email capabilities, address books, and a whole lot more, cell phones have come a long way since their first debut. Doing so could render important programs inoperable, corrupt the Windows operating system, and possibly prevent the computer from even starting. That's why using special deletion software is so important. Deletion programs will analyze a computer's operating system and installed programs to determine which files are crucial to computer function versus which files are safe to delete. We described shareware in another article, but because both commercial software and shareware require payment, they're the target of pirates who seek to make these kinds of programs free to use. Depending on their binding legal agreements, licensing typically allows the use of a single program on a single computer. exe files from the Internet since malicious programmers like to hide viruses in these types of files. .gif - This extension indicates another image file and it stands for "Graphics Interchange Format." .Gif files are often smaller than .bmp files (described earlier) and they're commonly found on Internet web pages.