What Is UX/UI Design?

UI/UX Design Principles

Chapter 1 · What Is UX/UI Design?

This site's own Creative & Design Tools subject already teaches Figma, Photoshop, and Blender — the tools. This course covers something none of those do: the actual thinking behind a good design decision. It's a companion to those tool courses, not a replacement for them — you'll still open Figma to build something, but this course is about knowing what to build and why before you open it.

Scope Note
Accessibility gets a light mention throughout this course as a design consideration, but the real depth on that topic already lives in this site's own dedicated Web Accessibility (a11y) course — that course is the one to reach for when accessibility itself is the focus.

UX vs. UI vs. Interaction Design

These three terms get used almost interchangeably in casual conversation, but they describe genuinely different layers of a real design problem:

TermWhat it actually coversA useful test question
UX (User Experience)The entire end-to-end experience of using a product — research, structure, flow, emotion, outcome"Did this actually solve the person's real problem?"
UI (User Interface)The specific visual and interactive surface a person touches — buttons, layout, color, type"Is this screen clear, consistent, and pleasant to look at?"
Interaction Design (IxD)How a person's actions and the system's responses are choreographed over time"When I do this, does the system respond the way I'd expect?"

UI is a real subset of UX — a beautifully designed screen (good UI) can still sit inside a confusing, poorly-researched product (bad UX). This course covers principles from all three layers, since a genuinely good design decision usually has to work at all of them at once.

A Real, Corrected History of "User Experience"

A Popular Claim Worth Correcting
It's often said that cognitive scientist Don Norman coined the term "user experience." The real, verifiable history is narrower than that: in 1993, when Norman joined Apple, he took the title "User Experience Architect" — the first documented use of the phrase "User Experience" in a job title. That's a real, significant milestone (it's a big part of why the term entered the professional mainstream), but it isn't the same claim as having invented the term itself, which the historical record doesn't actually support.

Norman's own real, larger contribution predates that job title: his 1988 book The Design of Everyday Things popularized ideas like affordances (what an object's own design suggests you can do with it) and feedback (how a system confirms an action was received) — concepts this course will build on directly in Chapter 4.

The broader field itself is older still. Xerox PARC's own research in the 1970s produced the graphical user interface concepts (windows, icons, a mouse) that Apple's 1984 Macintosh brought to a mass consumer audience — decades of real interface-design thinking before "UX" existed as a job title at all.

The Design Thinking Process

Design thinking is a real, widely-taught problem-solving framework, most associated today with the design firm IDEO and Stanford's own d.school. Its real intellectual roots go back further — creativity research in the 1940s-50s, L. Bruce Archer's 1960s "Systematic Method for Designers," and Horst Rittel and Melvin Webber's 1970s concept of "wicked problems" (problems too complex and interconnected to solve with a single, linear pass) — but it was IDEO and Stanford who packaged it into the five real, named stages most design teams use today.

1

Empathize

Research your users' real needs

2

Define

State the real user need and problem

3

Ideate

Challenge assumptions, generate ideas

4

Prototype

Build cheap, testable versions

5

Test

Try solutions with real users

A Real, Important Nuance
Design thinking is explicitly not a strict, linear pipeline. Stanford's own materials describe it as carried out "in a more flexible and non-linear fashion" — teams can run stages concurrently, repeat one, or circle back to an earlier stage the moment testing reveals the original problem definition was wrong. Treating it as a rigid five-step checklist misses the entire point of the framework.

Hands-On Exercises

Exercise 1

A colleague says "I already redesigned the UX of our checkout button — I made it bigger and changed its color." Explain, in your own words, why this description more accurately describes a UI change than a UX change, and what a genuine UX change to checkout might look like instead.

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Exercise 2

A teammate claims "Don Norman invented the term user experience in 1993." Explain, in your own words, what the real, verifiable historical record actually supports instead, and why the distinction matters.

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Exercise 3

A team finishes user testing (the Test stage) on a new onboarding flow and discovers users don't actually understand the core problem the product is trying to solve for them. Explain, in your own words, what the design thinking process says they should do next, and why that's only possible because the process is non-linear.

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Chapter 1 Quick Reference

  • UX — the whole experience; UI — the visual/interactive surface (a real subset of UX); IxD — how actions and responses are choreographed over time
  • Real correction: Don Norman was the first to use "User Experience" in a job title (Apple, 1993) — the historical record doesn't support him having coined the term itself
  • Norman's real, larger contribution: The Design of Everyday Things (1988) — affordances and feedback
  • The GUI itself predates "UX" as a term — Xerox PARC research in the 1970s, brought to consumers by the 1984 Macintosh
  • Design Thinking's five real stages: Empathize → Define → Ideate → Prototype → Test — explicitly non-linear and iterative, not a rigid checklist