Match Between System and the Real World
Use the words, concepts and order that your users already have, not the ones your database has.
Definition
Nielsen's second heuristic. The system should speak the user's language, with words and concepts familiar to them, and follow real-world conventions so information appears in a natural and expected order.
Expert heuristic. A review criterion developed by practitioners. Useful and widely taught, but evaluated by judgement rather than measurement.
On this page
Internal vocabulary leaks constantly
Product teams name things for the model: entity, record, workspace object, principal, tenant. Users name things for the job: file, invoice, teammate, folder. When the interface uses the internal name, every user has to translate on every encounter.
The fix is not to dumb language down. It is to use the vocabulary the user already uses for that concept, which you find by listening to support calls and research sessions rather than by writing a glossary in a meeting.
Where mismatch shows up
- Error messages containing status codes or internal exception names.
- Navigation labelled after the team that owns the feature rather than the job it does.
- Date and number formats that follow the server locale rather than the user's.
- Icons borrowed from a metaphor the audience no longer has, such as a floppy disk for save, which survives only because it is now a convention in its own right.
- Sort orders that follow database insertion order rather than any order a person would expect.
Do
- Name things the way users name them in support tickets and interviews.
- Follow real-world sequence: address before payment, not the reverse.
- Localise formats for dates, numbers, currency, names and addresses.
- Use plain words for destructive actions so the consequence is unambiguous.
Do not
- Expose internal identifiers or system states in user-facing copy.
- Invent brand words for standard actions.
- Assume a metaphor is universal. Test icons without labels before shipping them without labels.
In practice
Naming the object
B2B softwareA product that called records 'entities' in the interface generated a steady stream of support questions. Renaming them to the noun customers already used removed the questions with no functional change.
Real-world sequence in checkout
EcommerceDelivery choice before payment matches how people think about buying. Reversing it produces back-navigation and re-entry, and back-navigation in checkout is expensive.
Sources
Where a source establishes something narrower than the popular reading of it, the note says so.
10 Usability Heuristics for User Interface Design
J. Nielsen, Nielsen Norman Group, 1994, revised 2020
Continue from here
Each link says what the connection is, so you can tell a principle from an alternative from a thing people mix this up with.
Applies when you are designing
Why this works
The reasoning this entry rests on.
- Curse of KnowledgeCognitive bias
- Mental ModelsMental model
Applied through
Where this shows up as a concrete interface decision.
- Card SortingResearch method
- Information ArchitectureResearch method
- IconographyUI foundation
- Content DesignUX writing
- Error MessagesUX writing
- InternationalizationUX writing
- MicrocopyUX writing
- Voice and ToneUX writing
Practical example
A worked decision where this was the deciding factor.
- Fixing a Search That Returned NothingCase study
Short definition
The one-paragraph version, for when that is all you need.
- Conceptual ModelTerm
- Plain LanguageTerm
Related concept
Connected closely enough to change how you apply this.
- Consistency and StandardsHeuristic
- Help and DocumentationHeuristic
- Jakob's LawLaw