Editing Software (section)

==Quality and security==
{{main article|Software quality|Computer security}}
[[Software quality]] is defined as meeting the stated requirements as well as customer expectations.{{sfn|Galin|2018|p=3}} Quality is an overarching term that can refer to a code's correct and efficient behavior, its reusability and [[porting|portability]], or the ease of modification.{{sfn|Galin|2018|p=26}} It is usually more cost-effective to build quality into the product from the beginning rather than try to add it later in the development process.{{sfn|O'Regan|2022|pp=68, 117}} Higher quality code will reduce lifetime cost to both suppliers and customers as it is more reliable and [[maintainability|easier to maintain]].{{sfn|O'Regan|2022|pp=3, 268}}{{sfn|Varga|2018|p=12}} Software failures in [[safety-critical system]]s can be very serious including death.{{sfn|O'Regan|2022|pp=3, 268}} By some estimates, the cost of poor quality software can be as high as 20 to 40 percent of sales.{{sfn|O'Regan|2022|p=119}}  Despite developers' goal of delivering a product that works entirely as intended, virtually all software contains bugs.{{sfn|Ablon|Bogart|2017|p=1}}

The rise of the Internet also greatly increased the need for [[computer security]] as it enabled malicious actors to conduct [[cyberattack]]s remotely.{{sfn|Campbell-Kelly|Garcia-Swartz|2015|p=164}}{{sfn|O'Regan|2022|p=266}} If a bug creates a security risk, it is called a [[vulnerability (computing)|vulnerability]].{{sfn|Ablon|Bogart|2017|p=2}}{{sfn|Daswani |Elbayadi|2021|p=25}}  [[Software patch]]es are often released to fix identified vulnerabilities, but those that remain unknown ([[Zero-day (computing)|zero day]]s) as well as those that have not been patched are still liable for exploitation.{{sfn|Daswani |Elbayadi|2021|pp=26-27}} Vulnerabilities vary in their ability to be [[Exploit (computer security)|exploit]]ed by malicious actors,{{sfn|Ablon|Bogart|2017|p=2}} and the actual risk is dependent on the nature of the vulnerability as well as the value of the surrounding system.{{sfn|Haber |Hibbert|2018|pp=5-6}}  Although some vulnerabilities can only be used for [[denial of service]] attacks that compromise a system's availability, others allow the attacker to [[code injection|inject]] and run their own code (called [[malware]]), without the user being aware of it.{{sfn|Ablon|Bogart|2017|p=2}} To thwart cyberattacks, all software in the system must be designed to withstand and recover from external attack.{{sfn|O'Regan|2022|p=266}} Despite efforts to ensure security, a significant fraction of computers are infected with malware.{{sfn|Kitchin |Dodge|2011|p=37}}