UX, short for user experience, is everything a person goes through when they use a product: whether they can find what they came for, understand what to do, get it done without mistakes, and feel good about it afterwards. UX design is the work of shaping that experience on purpose, by understanding the people using a product and making decisions that fit how they think and behave.
This guide covers the basics of UI UX design: what UX design is and is not, how it differs from UI, what a UX designer does, the design process, the core principles and the skills to learn first. It ends with where to start. Every principle links to a UX law with a real screen to practise on, and two guides go deeper once you have the basics: Nielsen's 10 usability heuristics and the Gestalt principles.
The cognitive scientist Don Norman popularised the term user experience in the 1990s. When he joined Apple in 1993, his job title was User Experience Architect, and he has said he chose the phrase because human interface and usability felt too narrow: he wanted it to cover every part of a person's experience with a product, from the screen to the packaging to the manual.
In practice, UX design means deciding what a product should do and how it should behave for the people using it. Good UX is mostly invisible: people get what they came for and do not think about the design at all. Bad UX is noticed straight away, as confusion, mistakes or giving up.
UI, the user interface, is the part people see and touch: layouts, buttons, colours, type and icons. UX is the whole experience, including whether the product solves the right problem, how the steps flow, and what happens when something goes wrong. A beautiful interface can still be a bad experience, and a plain one can be a great experience.
| UX design | UI design | |
|---|---|---|
| Main question | Does this work for people? | Does this look and read right? |
| Focus | Needs, flows, structure, behaviour | Layout, visual style, components |
| Typical work | Research, user flows, wireframes, testing | Visual design, design systems, final screens |
| Success looks like | People finish the task easily | People understand the screen at a glance |
One screen, two jobs: the UI is how the three plans look, the UX is whether people pick the plan that fits them without second-guessing.
UI stands for user interface and UX for user experience. In many teams, especially small ones, one person does both, which is why courses and job titles often join them as UI UX design and UI/UX designer.
The common thread is judgment: choosing between options and being able to explain why one is better for the people using it.
Most teams follow some version of the Double Diamond, a model published by the UK Design Council in the mid-2000s. It has four phases, and teams loop back through them rather than following them once in a straight line.
| Phase | What happens | Typical methods |
|---|---|---|
| Discover | Understand the people and the problem | Interviews, analytics, observing people |
| Define | Agree what problem to solve | Problem statement, user flows, priorities |
| Develop | Explore and test possible solutions | Sketches, wireframes, prototypes, usability tests |
| Deliver | Build, launch and learn | Final design, handoff, measuring the result |
The first diamond is about finding the right problem, the second about finding the right solution. Skipping the first is the most common mistake beginners make: they design a good answer to the wrong question.
Jakob Nielsen describes usability with five qualities. They are a useful checklist for any screen:
UX laws are patterns in how people behave that hold across products. You do not need all of them to start. These six cover most everyday decisions:
Fitts's Law in practice: the main action is a large button at the bottom of the screen, where the thumb already rests.
Tools such as Figma matter less than they seem at the start. They are quick to learn; the judgment about what to design is not.
Reading only takes you so far: UX judgment grows by making decisions and seeing why they work or do not. UX Quest is built for that step. Each challenge puts a real product decision in front of you and explains the law behind the answer, and the Beginner challenges are free: a free account, no card.
Three laws behind everyday design decisions. Open one to see the screen and the challenge.
UX design is shaping how a product works for the people using it, so they can find what they need, understand what to do and get it done easily. It covers research, structure, flows and testing, not only how screens look.
UI (user interface) is the visible interface: layout, colours, type and buttons. UX (user experience) is the whole experience, including whether the product solves the right problem and how easy the steps are. UI is part of UX.
A UX designer learns what users need, defines the problem, maps user flows, sketches and prototypes solutions, tests them with real people and works with the team to build the result.
A common model is the Double Diamond: discover the people and the problem, define what to solve, develop and test possible solutions, and deliver the final design. Teams repeat steps as they learn.
Yes. Learn the core principles, review products you use, practise making and explaining design decisions on real screens, and build a few small projects you can show as case studies.
No. Knowing what is easy or hard to build helps you work with engineers, but UX design is about understanding people and making decisions, not writing code.