Open Source refers to software in which the blueprint, or source code, is available to anyone to change and improve. Ideally, they are made publicly available in order for users to add features to it or fix areas that may not have worked correctly. Open source software differs strongly from closed software or proprietary software in which the software can not be modified by anyone other than its creators. Although open source software can be useful and beneficial to users, malicious users have the ability to use open source software and distribute codes for viruses and other hacking methods. However, because users have the ability to view and edit the software codes, an argument can be made that open source brings less of a risk in terms of viruses. Because the codes of proprietary software can not be viewed by anyone other than its creators, these bring more of a risk in terms of computer viruses.