Co-workers are familiar with this temptation and they're often the ones who "share" purchased software among those who need it. However the same temptation also prompts others to knowingly or unknowingly buy bootleg copies of commercial software or registered shareware. As tempting as it is, it's still illegal and the punishments/fines for sharing commercial or registered software is too much for one to bear. Depending on how you elected to install Winzip or StuffIt, you may be able to right-click a .zip or .sit file and have the program extract its contents into a new folder for you. Compressing Files When you want to upload a file or email a collection of files to a friend, it's best to archive it as a . But when they're typed into a programming language and compiled to create a an executable file (a file ending with the .exe extension), they turn into a software application. As we mentioned earlier, you can use a programming language to control your computer. By using simple commands, you can program your computer to perform mathematical tasks, fill out web forms, compose an email message and send it off, or any number of other things. We're talking about shareware - software that you can try before buying. Shareware has a long history and was rather popular in the days where BBS (bulletin board systems) reigned the online industry. It hasn't gone anywhere, but its competition with commercial software is fierce - so fierce that it tends to fall on the back burner among new computer users. bmp - This extension indicates another image file that might have originated from Windows Paint program. .dll - This extension indicates a Dynamic Link Library which may contain additional programming code for software. Many different programs often share Dynamic Link Libraries and you'll find a bunch of them in the Windows/System directory (but don't ever delete them)! Despite his motivation or intention, his efforts were null. We wouldn't be surprised to learn if other motivations behind spreading viruses were similar to this person's, but that doesn't justify the damage that viruses do. Innocent people become pawns for the evil plans of others who've convinced themselves they're doing the "right" thing.