Human-Computer Interaction: Usability and Experience

• Human-Computer Interaction (HCI) is an interdisciplinary field focused on the design, implementation, and evaluation of how humans interact with computing devices.
• HCI aims to enhance productivity, safety, and entertainment in human-computer activities.
• HCI has expanded from computer interface design to encompass nearly all forms of information technology design.
• HCI has increased in prominence alongside computers' integration into daily life.
• Focus is maintained on designing computer interfaces that are high in usability and user experience, in addition to supplying functional computational abilities.

High Usability

• Constitutes the interactive design and operations through specific computer system criteria.
• Includes correctness, efficiency, safety, utility, learning, and retention.

User Experience

• Focuses on creating systems that enhance a person's overall involvement.

• Creates experiences that are satisfying, enjoyable, entertaining, helpful, motivating, aesthetically pleasing, and fun.

• Humans interact with computing devices through user interfaces, comprised of software (e.g., displays) and hardware (e.g., keyboards, mice).

• Interaction is an abstract model of how humans engage with computing devices to complete tasks.

• Interface is where two independent systems meet, act on, or communicate with each other.

Importance of HCI

• Usable and efficient interaction with computing devices leads to higher productivity.
• Poor interfaces hinder users from benefiting from even simple systems.
• Aesthetic appeal is critical for commercial success and usability.
• Seamless products and services provide a competitive edge.
• Apple products exemplify attractive design and a loyal customer base.
• HCI has significantly impacted computing history and daily life.
• HCI continues to redefine how humans view, absorb, exchange, create, and manipulate information technology.
• Spreadsheet interfaces drove business computing success.
• Web browser interfaces enabled the Internet phenomenon.
• Smartphones and other mobile devices are widely used.
• Body-based and action-oriented interfaces enhance computer games.

Principles of HCI

• Includes "user-centered design" which is the primary principle of HCI.
• Interaction and interfaces should meet the needs and capabilities of target users.
• Basic user information (gender, age, education, computing experience) is collected and analyzed.
• The goal is to determine user preferences, tendencies, physical and mental capabilities, and skill levels.
• This information informs the choice of interaction modes and interface design.
• Profiling the target user of a program within a company is important for design.
• Age brackets of software users in educational institutions should be known.
• Understanding computing experience of employees is important.
• Universal usability caters to a wide range of users, promoting humane interfaces.
• Universal usability is difficult to achieve due to the extensive requirements of multicultural societies.

Understand the Task

• The term "task" refers to the job to be accomplished by the user with the interactive system.
• Understanding the task is closely related to interaction modeling and user analysis.
• It involves sequence identification and structure of subtasks appropriate for users.
• Examples include formulating an interaction model for logging into a website and creating a conceptual model for system access in a corporation.
• It also encapsulates analyzing a user’s capability to navigate a program module

Reduce Memory Load

• Humans are more efficient with tasks requiring light memory load (short or long term).
• Light short term memory load is important for quick and easy task completion.
• Human short term memory capacity is about 5-9 specific pieces of information related to task completion.
• Light memory load leads to fewer errors.
• Limiting the number of menu items or tabs maintains user awareness.
• Keyboard shortcuts (e.g., copy/paste) facilitate quicker and more effortless navigation.

Strive for Consistency

• Consistency relieves long term memory load and applies to both interaction models and interface implementation.
• Inconsistent interfaces cause user confusion and inappropriate responses.
• Consistency and familiarity lead to higher satisfaction and preference.
• Examples include a consistent look within a gaming application and consistent interfaces between Microsoft PowerPoint and Word.

Remind Users

• Interfaces should provide constant reminders about important information or actions to refresh user memory.
• Feedback is associated with this principle, where the output of a system is used as an input back into the system.
• Examples include confirming credit card receipt in online payments and reminding users to perform system updates.

Prevent Errors/Reversal of Action

• Tasks should be completed without error.
• Interaction and interfaces should be designed to avoid user confusion and overwork.
• Examples include confirming user actions via pop-up menus and presenting only relevant information.
• Selection interfaces should be used rather than enforcing recall or full manual input.
• Easy reversal of actions (e.g., "Undo" button) enhances user comfort.

Natural Interaction and Interface

• Favoring natural interaction and interfaces reflects real-life actions and processes.
• Translating real-life actions into computer interactions can be complicated but achievable.
• Wii and Pokémon GO exemplify natural interactive interfaces.

Explore human-computer interaction (HCI), an interdisciplinary field focused on designing effective interfaces. HCI aims to boost productivity, safety, and enjoyment in human-computer activities. High usability and user experience are key.