open source software often lacks the debugging and security features available in commercial software. users must have the knowledge to use software that requires a lot of development work. open source software typically does not have a level of maintenance or support that is comparable to commercial software.
open source software may lack the features available in commercial software. however, there are many open source software packages available to perform specific tasks. software that is not available as open source may be available in a freeware or shareware package. for example, norton internet security is a commercial antivirus program, but the open source version of the software is available.
programmers may use a variety of testing methodologies to ensure that a software application performs as expected before it is released to users. this is especially important for software that is used in safety-critical applications. examples of testing methods include software testing and system testing. software testing involves the systematic exploration of a software application in order to find its weaknesses. system testing refers to the implementation of a test plan that can verify the integrity of the entire system. the general process of testing includes exploration, design, writing, execution, analysis, and maintenance. see also the profile for software engineer.
operating systems are the core components of a computer that provide a platform for computer software to execute. operating systems are responsible for managing computer hardware resources and controlling the operation of computer hardware and software. the operating system provides a uniform layer of services for applications and users. this includes the ability to start and stop programs, protect data, provide device drivers and other system services. see also the profiles for computer systems analyst and computer systems administrator.