A security bug is a software bug that benefits someone other than intended beneficiaries in the intended ways.Security bugs need not be identified, surfaced nor exploited to qualify as such. Some exploited ones, particularly viruses, have been known to wreak global damage at massive cost. A software bug is the common term used to describe an error, flaw, mistake, failure, or fault in a computer program or system that produces an incorrect or unexpected result, or causes it to behave in unintended ways. Most bugs arise from mistakes and errors made by people in either a program's source code or its design, and a few are caused by compilers producing incorrect code. A program that contains a large number of bugs, and/or bugs that seriously interfere with its functionality, is said to be buggy. Reports detailing bugs in a program are commonly known as bug reports, fault reports, problem reports, trouble reports, change requests, and so forth.