Richard's Blog: Ten Golden Usability Rules

Tuesday 5 January 2016

Ten Golden Usability Rules

Taken from Jakob Nielsen in his book `Usability Engineering`.

Use simple and natural dialog/language. Since every additional feature or item of information on a screen is one more thing to learn, one more thing to misunderstand and one more thing to search the user interface should be simplified as much as possible. Less is more.
Use language that fits the user group. The language should be based on user's language and not the system-oriented terms. Translation from one language to another is more than just words. Time, current, phrases, metaphors, measurements all must fit the culture of the user group.
Minimize the load on short-term memory. Users should not have to remember information from one part of the interface to another. Instructions of usage should be visible or easily retrievable whenever appropriate.
Make the graphical user interface coherent and consistent. The same action should always have the same effect.
Give the ability to use shortcuts. Accelerators (unseen by novices) may increase the speed of operation and therefore efficiency through using things like; function keys, command keys, macros, etc.
Give feedback to the user's actions. The feedback should be given within reasonable time which would make the system more pleasant. At a 0.1s delay the user feels the system is responding immediately, 1s delay is around the limit that humans flow of thought will stay interrupted and a 10s delay is the limit to keep user's attention focused on the dialog. As always the user should always have feedback about waiting times, which in itself increases the time people are willing to wait.
Avoid error situations. Ask the user for confirmation on actions, avoid having similar commands in the interface.
Give clear exit marks. Users make mistakes, so providing an "emergency exit" to leave an unwanted state without having to go through extended dialogue is essential. Eg. Cancel should be offered when the operation takes a long time and backing up actions provided in navigation bars.
Give clear and understandable error messages. Similar to 2, provide the user with information that is precise and discrete. They should always be polite and not intimidating for example "ILLEGAL, FATAL ACTION, JOB ABORTED!" is bad.
Give clear help and understandable documentation. List the concrete steps that should be carried out, but the help should not be too large.