A project management program that you're interested in may require a specific operating system, like Windows XP for example. And although this program may install just fine on a Windows 98 machine, it will generate a multitude of errors once its started. Insufficient memory will cause errors as well. Instead of speaking to a human being, chances are that you spoke to a computer that not only responded to what you said and followed the commands that you gave it, it also asked you for more information such as your full name or credit card number. In this case, a person (such as yourself) operated a computer without even knowing it! " Click "OK" and you'll notice that the files in Windows Explorer show a dot and group of three letters after their names. That dot and group of three letters is known as an "extension," and the extension explains what kind of file it is. A file could be a plain text file, an image, a sound, a video, or program. Even the operating system of a computer has a help file and it really should be the first place to look for answers. Help files are designed not only to guide the usage of a computer, they're also designed to solve problems. Inside a help file, look for a section called, "Troubleshooting" (or something similar) when you need to resolve an issue. Let's say that a brand new computer is a batch of plain dough - waiting to be flavored and baked into something useful. If we want to use this dough to make a delicious batch of chocolate chip cookies, we would need to "accessorize" this dough with chocolate chips and a little brown sugar. If we want to use this dough into in a warm loaf of sesame seed bread on the other hand, we'd need to "accessorize" the dough with yeast and sesame seeds. The commands in a program are pretty useless unless they have some data to act on so programmers either give the programs some data to work with (list of names or numbers for example) or they make the program generate it's own data. Sometimes, the data comes from an outside source like the Internet or the computer that the program runs on.