Gabriel Spitz 1

What Is The User Interface Design

Lecture # 2

Gabriel Spitz 2

What is the User Interface (UI)

A user interface is the means and methods that we provide to the users to achieve their goal

The user-interface always includes:o A concept of what the user is trying to achieve

o A goalo Process or flow - the sequence of steps by which

an intent can be achieved o How will it happen

o Mechanisms that are used to control and manipulating objects in the work area o In what way

o Language, images and controls used in communicating between the user and the applicationo Using what means

Gabriel Spitz 3

Example of User Interfaces

Gabriel Spitz 4

What is included in the User Interface

User Interface includes more than the functionality it offers the user. It also includes

Physical characteristics – Size, resistance

Perceptual/Cognitive characteristics – Color, font size, label, work flow

Conceptual characteristics– What is this like

When designing a user interface we need to consider all of the above aspects

Gabriel Spitz

User Interface Design

UI

Scope

Concept

Activity Flow

Representation

Presentation

Needs Experience

Predictability

Convenience

Efficiency

Personal

Trust

Human

Task

Expectations

Usefulness

Gabriel Spitz 6

Interfaces are Everywhere

Interfaces are used in controlling or manipulating

Products – PIM, Cell Phones, Cars, etc.

Applications – Excel, Word, etc.

Our environment – Thermostat, Appliances, etc.

Interfaces are the medium through which the user communicate with the computer application

Gabriel Spitz 7

Controls

Displays

Procedure

Guidance-labels

UI Example

Watch

Gabriel Spitz 8

UI Example

Telephone

Controls

Displays

Procedure

Guidance-labels

Gabriel Spitz 9

UI Example

Controls

Displays

Procedure

Guidance-labels

Gabriel Spitz 10

UI Example

Kiosk

Controls

Displays

Procedure

Guidance-labels

Gabriel Spitz 11

Importance of the Interface

The “quality” of the interface design directly drives the user experience

user attitude and satisfaction

user performance

safety

Poor user interface can have serious consequences

Gabriel Spitz 12

Poor Interface – Can Ruin an Election

Florida Ballots (2000)

Users could not figure out How to use –Poor mapping between stimulus & response

Gabriel Spitz 13

Poor Interface – Can Ruin your Dinner

Poor Mapping

Gabriel Spitz 14

Poor Interface – Can Ruin a Product

Bob

Microsoft 1995

Users simply did not like this interface –

User satisfaction

Gabriel Spitz 15

Poor Interface - Can be a Safety hazard

Negative transfer of training resulting in many errors

Renault 4 circa 1970

Gabriel Spitz 16

Poor Interface - Can Ruin a Trip

Lavatory sink – It is difficult to use Performance

Incompatibility between control design and task

Gabriel Spitz 17

The Importance of Usable Interface

o From a user’s perspective there is no good user interface in the absolute sense only usable and useful interface

An interface is bad or good only to the extent that it hinders or supports users in performing a specific task in a specific environment

Poor interface = Poor product/application

Gabriel Spitz 18

What is a Usable Interface

Our goal is to design the user interface for products so they enable users to achieve their intentions in an easy and pleasant way

An interface is considered usable if it:Helps user achieve their goal

Easy to learn

Easy to use – e.g., recall vs. recognition, simple

Facilitates performance – speed, errors

Fun to use

These aspects of the interface are also called Usability Indicators

Gabriel Spitz 19

Usability of an Airline Kiosk

Key usability indicators Goal achievement – to obtain a boarding pass (but sometimes to get onto an earlier flight)Learning - no learning requiredEase of use – system leads users (hand holding)Performance – not applicable (from passenger perspective)Fun – nice to have, but not critical

Rarely can we maximize all of them