Editing Web usability (section)

===Nielsen's 10 heuristics===
[[Jakob Nielsen (usability consultant)|Jakob Nielsen]]'s [[Heuristic evaluation|heuristics]] are widely adopted in [[User interface design|interface design]]. It provides expert reviewers with a set of principles to discover usability problems and then categorize and rate them in a quick way. This set of heuristics includes visibility of system status, match between system and the real world and so on. According to Nielsen, there are 10 general principles:<ref>{{cite book |last1=Nielsen |first1=Jakob |title=Heuristic evaluation of user interfaces |date=April 1–5, 1990 |publisher=Proceeding CHI '90 Proceedings of the SIGCHI Conference on Human Factors in Computing Systems |location=Seattle, Washington, USA |isbn=0-201-50932-6 |pages=249–256 |edition=New York, NY, USA ©1990 }}</ref>

* Visibility of system status: the users should be informed by a system all the time that people can make better decisions.
* Match between system and the real world: the systems' language should be similar to users' language.
* User control and freedom: It happens many times that users choose the wrong system functions by a mistake, therefore, the system needs to contain the "emergency exit" to give an option for users to leave the unwanted state without any problem.
* Consistency and standards: the users have to be aware that different words, actions and situations can mean the same thing.
* Error prevention: System should have a careful design that can prevent a problem that can occur in the first place.
* Recognition rather than recall: the system should have the actions and options visible so the users do not need to memorize everything from previous steps. Instructions about the system usability should be always visible.
* Flexibility and efficiency of use: the system should have an accelerator to help experienced and inexperienced users to make work faster and easier.
* Aesthetic and minimalist design: the systems needs to contain only relevant and useful information. The information should be clear and short.
* Help users recognize, diagnose, and recover from errors: the error messages should be presented in a clear language and understandable form (no codes), and suggest the solutions.
* Help and documentation: the information about help and documentation should be easy to find and should focus on the users' tasks.