A/B Testing

Also called split testing, This is the practice of comparing two different versions of a web page or a screen with a single variable online to find out which one performs better.

Adaptive design

Collection of layouts designed specifically for different devices. it detects the device type being used and displays the layout designed for it. It means you’ll see a specific version of the website which has been optimized for mobile, desktop, or tablet.


A visual clue telling us what an element can do. For instance, a door handle is an affordance designed to tell us it can be pulled of pushed. In UI affordances help communicate what can or cannot be done on a screen.


Agile is an incremental approach to software development. Instead of building the entire product at once, Agile breaks it down into smaller bits of user functionality and assigns them to two-week cycles we call “iterations.”


Analytics measure user behavior on a site. It helps better understand and interpret patterns of behavior on a product.


Google’s open-source mobile operating system. Visually, it is characterized by Material Design, a design language developed by Google in 2014.


Application Programming Interfaces, or APIs, are pieces of software that help different applications communicate with each other. Products develop APIs to let you access and read the information on their server easily.


Avatars represent users online who have not uploaded an image for themselves. You’ll commonly see them in comment threads or in games.


Back-End Development

Part of software development that relates to the server and database side of the development process.


A prioritized list of tasks to be completed.

Benchmark Study

A study where participants perform certain tasks on a company’s product and its competitors’ products. The measured results can help establish best practices, form baseline performance metrics, identify problem areas, and build a vision and direction for product strategies.


Navigation element in UI that helps users orient themselves within a website or move to one of the higher-level pages.


Mistakes in software causing a product to malfunction, glitch, and even crash.


Call to Action (CTA)

A word, phrase, or UI element that stimulates users to interact with a product in the way it is designed for. CTA elements are the interactive controls such as buttons, tabs, or links that enable users to perform the expected action.


Data stored temporarily in a web browser or other app for later use. For instance, recent searches or visited websites are stored in cache memory.

Card Sorting

A research technique that helps improve the Information Architecture of a site and validate the findability of content or functionality of a website. Card sorting helps ensure that the way the information is structured on the website matches users’ mental models.


A way of interacting with a system via a chat interface. For instance, you can try to get help with customer support chatbot.

Clickstream Analysis

Tracking and analysis of how users click their way on a website to complete a task. Clickstream is a path of clicks users took on it to accomplish a goal. This analysis reports user behavior such as routing, stickiness, where users come from, and where they go from the website.


Content Management System is a software to manage the creation and modification of digital content.

Color Contrast

The difference between the two colors. Black and white create the highest contrast possible. Colors can contrast in hue, value, and saturation. Proper use of contrast is crucial for making the content and UI accessible to every viewer.

Color Wheel

A circle that shows the relationships between primary colors, secondary colors, and tertiary colors. Designers use 3 primaries: red, yellow, and blue arranged at three equally spaced points around the color wheel.

Context of Use Analysis

A research method that analyses personas, user flows, wireframes, content maps, site maps, and content strategy to create a contextual understanding of users’ behavior.

Corporate Identity Guideline

A set of rules and guidelines that defines how your company’s brand, image, and messaging are delivered to the public and particularly to your target audience. It contains the rules for consistent typography, color use, and logo placement.

Conversion Rate

The percentage of users that complete targeted transactions on a website or in an app. The conversion rate can tell how many users bought an item.

Concept Testing

A process of getting an idea evaluated by your target audience before it becomes available to the public, usually via user surveys.

Content Strategy

A process of planning, development, and management of content for a website – written or in other media.


Customer Relationship Management software systems that help manage business processes, like sales, data, and customer interactions.


Cascading Style Sheets is a style programming language used to define how a website should be styled.

Customer Experience (CX)

A multitude of different interactions a user has with a brand through its different channels and products, and how the user feels about them.

Customer Journey Map (CJM)

A tool designers and product teams use to see what their customers really want. A CJM tells the story from initial contact through engagement and the long-term relationship. It uncovers users’ feelings, motivations, and questions at each touchpoint.



An approach, where data is used to inform decisions. Designers tend to make data-driven decisions based on user data in order to generate better solutions, that will address insights uncovered in this data.

Design Dept

Design discrepancies accrued over time due to adding new elements, components, and patterns to UI.

Design Thinking

A design methodology that is used for solving design problems using a human-centric approach. The design thinking process is iterative and typically includes 5 phases: discovery, definition, ideation, prototyping, and testing.

Design Validation

A method that is used to ensure that a design concept meets the expectations and intentions of its users. Design validation is an integral part of the design iterative process.

Diary Study

A qualitative research method that is used to collect information about users over time by asking them to write down their everyday activities in a journal.

DPI (Dots Per Inch)

A degree of density of a print or video image, in particular the number of individual dots that can be placed in a line within the span of 1 inch. Today the term is often misused, usually to mean PPI, which stands for Pixels Per Inch.


Effectiveness Ratio

A quantitative type of metric that helps determine whether users successfully completed a given task on a website, app, or prototype.

Efficiency Ratio

A quantitative type of metric that helps measure how long did it take for users to complete a given task on a website, app, or prototype.

Eye Tracking

A user testing and research methodology that allows measuring how users interact with a UI through tracking their pupils’ movement and observing their visual attention.

End User

A final customer of your app, website, or product. Typically represents the participants or subjects of UX research studies.

Empathy Map

A collaborative tool that enables designers and researchers to visualize user behavior, attitudes, and feelings. It is based on user personas and is commonly used in the research and definition phases of the design process.

Empty State

A state of a UI element or a screen, when no content is available. In this case, designers use to place some contextual content and CTAs to drive user’s engagement.

Error State

A state of a UI element or a screen showing that something went wrong. A well-designed error state communicates the error, its possible reason, and a way of rectifying it.


Flat Design

A minimalist UI design style that is characterized by simple, 2-dimensional elements and vibrant colors.


A way of depicting the steps a user can take to accomplish a task on a website, app, or product.

F-Shaped Pattern

The way users skim through a page in order to consume content on it. Naturally, people start from the upper left corner and skim through the content in 2 horizontal stripes and then move their eyes down vertically. Hence F-shape.

Fishbone Diagram

Or Ishikawa diagram is a couse-and-effect diagram that helps track down the reasons for user issues in a product. It resembles a fish skeleton with a problem at its head and cases for the problem feeding into the spine.

Fitt’s Law

A mathematical formula that predicts how long it will take to point at a target based on its size and proximity. The smaller and farther is the target, the harder is to interact with it for a user.

Focus Group

A way of getting insights from a target group of users through a moderated discussion. Questions are designed to collect feedback about concepts, prototypes, users, tasks, and strategies.


Golden Ratio

A mathematical proportion between the elements of different sized which is most aesthetically pleasing for human eyes. Two quantities are in the golden ratio if their ratio is the same as the ratio of their sum to the larger of the two quantities.

Gestalt Principles

Principles explaining how people perceive groups of objects based on visual similarity, proximity, continuity, and closure.

Grid System

A system of vertical and horizontal lines that helps organize content and visual layout. It helps achieve order, economy, and consistency. 


Integration of game-design patterns and principles into products in order to drive user engagement.


Collaborative development platform used mainly by developers that provides version control and code management functionality.


H.E.A.R.T. Framework

System of qualitative and quantitative metrics invented by Google. It classifies UX metrics into 5 categories: happiness, engagement, adoption, retention, and task completion.

Heat Maps

Color-based representation of the user’s focus zones generated usually by eye-tracking software and hardware. Usually, red areas signify the zones users interact with the most.


Hypertext Markup Language – a standard programming language used to build websites.

Human-Computer Interaction (HCI)

HCI is a science about design and user of computer technology. It explores how people interact with interfaces and computers.

Hybrid App

An app that combines both native and web technologies by placing a web app in a native app shell. It can be downloaded and installed locally from an app store, and the shell is able to connect to the capabilities of a mobile platform through a browser embedded in the app.

Heuristic Evaluation

Usability inspection method for digital products that helps identify usability problems in the UI. It is based on usability principles (the “heuristics”) created by Jakob Nielsen.

Human Interface Guidelines (HIG)

Set of recommendations for iOS/macOS application developers and designers. It helps improve the experience for the users by making interfaces more intuitive, learnable, and consistent.


An arrangement of items in which the items are represented as being “above”, “below”, or “at the same level as” one another.


Inclusive Design

The design process in which a product is optimized for a specific user with specific needs.

Information Architecture (IA)

Art and science of organizing, structuring, and labeling content in an effective and sustainable way, so that users can easily adjust to the functionality of a product.

Interaction Design (IXD)

The practice of designing interactive digital products, environments, systems, and services.


Visual representation of commands, devices, directories, actions, and other entities in the UI. Icons maximize comprehension and reduce cognitive load by calling attention to a particular element. Icons are meant to be simple, visual elements that are easily recognized.


Mobile operating system created by Apple Inc. exclusively for its mobile hardware. iOS powers iPhone, iPad, Apple Watch, and other devices.

IP Address

Internet Protocol Address is a unique number comprised of numbers and periods, that is used to identify each device utilizing the Internet Protocol to communicate in a computer network.


Process of separating product development into small parts and constantly improving each of it based on users’ feedback and other data.

Interactive Prototyping

A practice of exploring and evaluating design ideas by building an interactive experience that helps other people see your vision. An interactive prototype is a sequence of screens linked together to mimic a real product’s UX.


Justified Text Alignment

Text aligned the left margin, and letter- and word-spacing is adjusted so that the text falls flush with both margins.



Key Performance Indicator – a measurable value that helps understand and track how well a product is doing. Designers use UX metrics to inform KPIs for their products.


Landing Page

A page that a user lands on. Landing pages are key parts of marketing campaigns and are used to communicate the value proposition of an offer and drive user conversion. Typically, an LP is a web page that contains a description of an offer, social proof, CTAs, and other elements.

Lean UX

A design process based on the Agile approach, that implies a collaborative user-centric workstream prioritizing “learning loops” (building, learning, and measuring) over design implementation.


Vertical space between lines of text.


Material Design

Design language created by Google and used in Android devices and on the web.

Mental Model

The way users understand something (product, flow, functionality, layout, etc). The more a user’s mental model is aligned with a product UX and functionality, the better it will be for them to use it.


Small portions of text in UI that help users navigate it. Usually related to button labels, placeholders, tips, alerts, and so forth.

Mobile Web

This is the same web but accessed from mobile devices.


A static representation of a product or its fragment.


Minimum Viable Product – essential set of features included in the first launch of a product to address the key user needs and deliver the key value. Products are often launched as MVPs to release fast and gather valuable user feedback.


A diagram used to visually organize information. A mindmap shows hierarchical relationships among the parts of the whole.


Net Promoter Score (NPS)

A measurable indicator that shows how loyal users are towards a brand or product. The level of loyalty is defined by the question: “How likely would you recommend something to a friend or colleague”. Is calculated by using a 0-10 scale.

Neural Network

An artificial network of circuits of neurons, inspired by biological neural networks that constitute animal brains. It’s a series of algorithms that consume data and generates the best possible results for specific needs.


Online Survey

A practice of collecting customer, user, and employee feedback. It’s often used in conjuction with UX metrics in research studies.

Open Source

A code, application, or another digital asset that is available for public use, and is free. People can take it, modify it, utilize it however they need without any restrictions.



A representation of the product’s target user. This is a collective portrait of the user describing their traits, social status, personal details, needs, and problems relevant to the product UX. Personas are created based on different research studies.


A smallest measurable unit on a digital screen, also a physical point on a raster image.


An early model of a product mimicking its functionality. Prototypes can have different levels of quality and types of execution: paper prototypes, interactive prototypes, and others.

Prototype Testing

A practice of testing of any kind of designs and prototypes with the target users in order to validate design decisions and collect users’ feedback.


Qualitative Research

A type of research that relies on unstructured and non-numerical data. The data include field notes written by the researcher during an observation, interviews, and questionnaires.

Quantitative Research

A methodology used to test theories and assumptions based on numerical and statistical evidence. UX researchers sample a certain number of people to indirectly receive measurable, bias-free data about users in relevant situations.


Remote Usability Testing (RUT)

An unmoderated task-based study on a website or app with remote participants. It is conducted with simultaneous participants at different times, using their devices. RUT saves time and costs for the companies and improves the frequency of testing.

Return on Investment (ROI) of Design

A performance measure used to evaluate the ratio between net profit or outcome and cost of investment. In UX design ROI is used to measure the impact of design on users and businesses.

Refactoring of code

Process of cleaning up code without affecting the functionality of an app, but increasing its quality. It is implemented incrementally, in small portions.

Responsive Web Design (RWD)

The ability of a website to adapt to the device they are being displayed on. In this case, a single layout is adjusted to the screen’s size in order to create an optimal viewing experience.


Screen Recording

A process of recording user actions on a screen during user testing study. Used for understanding the user’s behavior.

Screenshot Click Testing

A method of tracking users’ first impressions and first clicks on a wireframe or website screenshots. The users’ clicks are recorded and later on presented as a heatmap, displaying all the clicks.


A low fidelity drawing on a paper or any other type of canvas to explore ideation ideas. Designers usually use sketching to jot down the first raw design concepts.


Software as a Service – a software distribution model in which an app is licensed on a subscription basis and hosted in the cloud. Its customer can access it through the web.


Agile software development framework.


Search Engine Optimization – a process of improving the website’s findability in organic search results. It includes creating useful and semantic content based on words and phrases users use in search queries related to product, brand, or service.

Site Map

A visual representation of a website’s structure and hierarchy.


A program and other operating information used by a computer or cloud.


In Agile it means a period of time required to complete certain tasks.


A visual representation of a user’s experience with a product. It uses a film technique and depicts the user’s experience as a sequence of screens, like in comics.


Scalable vector graphics – an image format containing two-dimensional graphics that can be manipulated and animated with code.


Task Completion Rate (TCR)

One of the fundamental usability metrics. It quantifies the effectiveness of an interface by measuring whether the study participants are able to accomplish a given task.

Task Efficiency

A UX metric used to measure how users are able to achieve a given task with minimal resources.

Task Analysis

A process of defining tasks a user takes to complete a given goal. Usually, it’s done during the early stages of product development and helps pinpoint and communicate problems in the UX.

Technical Dept

Product teams accrue technical dept whenever a poor but an easier solution is favored over a better yet but more time-consuming alternative. Ultimately the poor solutions pile up and need to be cleaned up, generating work.


The art of arranging letters and text in a way that makes the copy legible, clear, and visually appealing to the reader.

Task-Based Research

Typically this is a usability study that based on certain tasks given to its participants. It requires a moderator and an optional observer. An important aspect is that the participants are not in their natural context of use, which can result in imprecise results.


A qualitative research method used in research studies, when participants are asked to vocalize their thinking and actions and think out loud as they try to accomplish tasks.

Tree Testing

A usability technique used to evaluate findability, labeling, and organization of information architecture and website’s structure. It helps learn how users can find items in a hierarchy.

True Intent Study

A study of who your users are and what they are trying to accomplish as they interact with your product. This tool captures users’ attitudes and behaviors in the context of what they are trying to do in the app, which allows making better-informed decisions about product changes.

Three-Click Rule

The rule saying that the users will likely abandon a website if they are unable to complete their task within 3 mouse clicks.


Usability Testing

A practice of evaluating the usability of an app or website by giving specific tasks to its participants and detecting usability barriers.

UX Analytics

A set of data about your user that provides reliable insights about their experience helps you improve your product.


An individual who utilizes your product.

User Flow

A path taken by a user on a website or app to complete a task.

User Experience

What a user experiences when interacting with a product. UX impacts the entire customer experience and user’s brand perception.

User Experience Design

A process of continuously optimizing the usability, accessibility, and satisfaction given the interaction between users and a product. It includes user research, visual design, information architecture, interaction design, usability.

UX Management

A discipline that provides business outcomes through optimizing the experiences that the user has while interacting with the company’s brand. It shows the impact a good UX can have on business and why it is worth to invest in UX research.

User-Centered Design (UCD)

An approach to designing a product in which the end user is in the center of the process.

User Scenarios

Hypothetical circumstances used to frame and guide the user to follow a certain task path.

User Interface (UI)

A set of commands and controls through a user communicates with a system. A UI can be graphical, voice, conversational, physical.

UI Element

Part of UI that is used to trigger specific actions or communicate information with the user.

UI Pattern

A reusable UI solution to common usability problems that includes a set of UI screens, elements, and actions a user might utilize to accomplish a task.

User (Customer) Journey Map

A visual representation of the process a user goes through in order to accomplish a goal. It captures the stages the user goes through, the tasks executed at each stage, user feelings, problems, and product opportunities.

User Story

An action different kinds of users might take in a product. It’s based on the model: “As a [kind of user], I want to [action], to be able to [get an outcome]”.


Visual Design

Use of imagery, color, shapes, typography, and form to enhance usability and improve the user experience.

Voice of the Customer (VOC)

In-depth process of capturing customer’s expectations, preferences, and aversions through surveys.

Virtual Reality (VR)

An immersive simulated experience that can be similar or different from the real world. A user is immersed in a simulated experience via hardware – e.g., headsets – and software.

Vertical Rhythm

A concept of keeping spaces between elements on a screen consistent with each other. Derives from print design and typography.



A software development process, where each phase must be completed before the next phase can begin.

Web (WWW)

World Wide Web – an information system where documents and other web resources identified by Uniform Resource Locators, which may be interlinked by hypertext and are accessible over the Internet.


A low-fidelity or simplified sketch of a page or screen of an app. Is created to define the screen’s architecture and layout.

Whiteboard Interview

A part of the interview process, where a candidate is given an exercise and should solve it by demonstrating their communication skills and problem-solving acumen.

White Space

Or negative space refers to the blank or empty space on a screen. The wise use of white space constitutes a good visual composition and user experience.



A CSS property specifying the stack order of an element. An element with greater stack order is always in front of an element with a lower stack order.