Graphical User Interface (GUI) Basics

Study Notes

GUI is a type of user interface that allows users to interact with electronic devices via graphical icons and visual indicators.
It's a critically important aspect of software engineering, as users often judge a system based on its interface, not its functionality.
Poorly designed interfaces can lead to catastrophic errors and discourage software use.
User interfaces (UI) are the key part of applications because they primarily interact with the user and control the system.
User interfaces, by design, need to be considerate of the intended user (e.g. designers aren't the intended user; usability is vital.)
User interfaces require consideration and design because: Ease of learning & use, ability to remember the interface, executing tasks effectively, minimal error rate, high user satisfaction.

User interfaces typically consist of a screen, fields (e.g., first name, last name), labels, and buttons.
Visual elements (background and layout) are crucial for visual appeal.
User interface elements are designed with input validation and control processes to ensure data integrity and user expectations.

Easy to learn and remember interfaces save user time.
High-productivity interfaces allow fast and effective task execution.
Minimal error rate designs with good feedback improve user experiences when errors occur.
High user satisfaction provides confidence to the user they are using a useful interface.

Modern user interfaces are visually appealing and effective, having better organization and usability. Examples of text properties include font selection, size, and color options.

Conceptual Elements (60%): User experience, power of actions in the interface, flexibility and growth of the interface.
Look (10%): Aesthetic appeal, color scheme, font selections, overall visual perception, and consistency.
Feel (30%): Usability, ability to match behaviors with functionality, positioning, user-accessible items, navigation, user feedback, interface labels.

System interfaces are concerned with input/output operations requiring minimal human intervention.
User interfaces are primarily concerned with input/output operations requiring human intervention, ensuring usability, and containing the devices that users interact with.

User familiarity: Interfaces should be based on user-oriented terms and concepts, avoiding computer-specific terms (e.g., "directory," "file identifier").
Consistency: Formatting, appearance of commands and menus, and command punctuation must maintain consistent formats.
Minimal surprise: Consistent operations for commands (e.g., "yes" or "no").
Recoverability: Handle user errors and offer ways for users to recover from errors (e.g., "soft deletes," undo/redo functionality).
Provide good error messages, keep errors concise and consistent.
User guidance: Help functions, indexes, topical guides, online manuals & tutorials.
User diversity: Consider different user experiences (novice/expert), accessibility and physical disabilities (e.g., customizable font sizes, automated reading programs).

Iterative process with close collaboration between users and designers.
Core activities include user analysis, system prototyping, and interface evaluation.
Use user analysis to understand user needs and tasks.
UI design is a staged process. Start with paper prototypes, then develop digital prototypes.
Design prototypes and test them with real users to evaluate the user experience (UX).
Refinement and improvement are crucial.

Evaluation is a crucial part of the UI design process to assess suitability.
Evaluation should be carried out by real users to comprehensively evaluate the design.
Low cost techniques are useful (e.g., expert evaluation, walkthrough).

Minimize the use of multiple fonts; use a maximum of 3 or less.
Wider fonts (e.g., Times New Roman) are easier to read than fixed-width fonts (e.g., Courier).
Use a combination of upper and lowercase letters effectively.

Space or distance can be used effectively to group elements in a user interface.
Colors can support grouping as well.

A team of experts is ideal, including graphic designers, interface designers, technical writers, marketing/test and software engineers, and end-users.