1. Foundation of HCI Flashcards
HCI
Field of study that researchers design and the use of computer technology focused on interfaces between people(Users) End computers
User
A individual or a group of People working together who use the computer or a system
Computer
Any technology ranging from desktop computers to large scale computer systems
Interaction
The way through which users use the computer.
Goals of HCI
- Usability
- user satisfaction
- accessibility
- productivity
- safety and security
- adaptability and flexibility,
- emotional and social well being
- task support,
- engagement and fun
- innovation
Usability
Usability
Usability is one of the key concepts in HCI. It is concerned with making systems easy to learn and use. A usable system is:
• easy to learn
• easy to remember how to use
• effective to use
• efficient to use
• safe to use
• enjoyable to use
Input output channels in humans
Personal interaction with the outside world occurs through information being sent and received. A person interact with a computer is that if user sends the information to the system it becomes input for computer And the information given by the computer becomes the output for the computer and vice versa
- Major senses, such as sight hearing, touch, taste and smell And from these site hearing and touch are important in Hsci
- There are also a number of effectors, including limbs, fingers, eyes, head and vocal system, in which fingers play primary role in Hsca
Vision
Hearing
Touch
Movement
Human memory
it contains our knowledge of actions and procedures
types of mem:
1 sensory mem
acts as buffer for stimuli received through senses..like
iconic mem——visual stimuli
echoic mem—–aural st
haptic mem——-touch
- These memories are constantly overwritten
2 short-term mem
Working memory that articles scratchpad for temporary recall of information.
- This memory can be accessed rapidly (70MS) and decays rapidly (200 ms)
3 long-term mem
Factual information, experimental knowledge, procedural rules of behaviour—- in fact, everything that we know are stored here forever
Thinking reasoning and problem solving in humans
- Humans can do the activities even when the information is partial or Unavailable
reasoning
- Process by which we use the knowledge To draw conclusions or infer something new about the domain of interest
1 Deductive
derives the logically necessary conclusions from the given premises
2 inductive
Generalising from the cases we have seen to infer information about cases we have not seen
3 abductive
Reasons from a fact to action or a state that it caused
- It derives explanations for the events we observe
problem solving
Ability to Adapt the information when we have to deal with new situation
- Gestalt’s view on problem solving in humans is that They involve both reuse of knowledge and insight
computer
“C:\Users\mural\OneDrive\Desktop\BSCS\3rd year\6th sem\HCI\1. unit.docx”
Memory in computers
short term mem
Lowest level of computer memory are registers on the computer chip
- Most currently active information is held in silicon chip random access memory (RAM)
- Typical access time is in the order of 10 nanoseconds
discs and long term memory
For most computer users, the ltm consists of discs possible with small tapes for backup
- The two main kinds of technology used in discs, magnetic discs and optical discs
Compression
Compression techniques can be used to reduce the amount of storage required for text bitmaps and videos which are highly redundant
Storage format and standards
The most common types of data stored in interactive programmes are text and bitmap images and video audio
- Basic standard for to text storage is ASCII(American Standard code for information exchange)
processing and n/wg
Shows how accuses interact with the digital system both locally and across distributed systems.
processing
- Refers to house systems handling inputs manage tasks and generate outputs in response to user actions.in HCI processing efficiency and responsiveness significantly affect the user experience. Key aspects include:
1 Real time processing
Computers need to process inputs Instantly to maintain smooth interaction as delays can frustrate the users
2 parallel processing
Many modern applications support multitasking where different processes run simultaneously, ensuring the system can handle multiple user actions or data inputs efficiently
3 task scheduling
How Tasks are managed and cured by the system is crucial. As it ensures that user prioritised tasks get necessary processing resources
4 interactive feedback loops.
HCI processing is tightly coupled with feedback loops where users inputs lead to immediate visual auditory or haptic feedback.
Networking in HCI
Enables connectivity and data exchange between different devices and users
1 Latency and bandwidth
- Low latency networks provide faster response time, improving real time interaction experience
- adequate bandwidth also needed for data-heavy applications
2 cloud based systems
- Many modern interfaces rely on cloud computing for processing and data storage, Affecting how uses interact with the distributed systems
- hence networking quality determines how quickly the users input reaches the cloud and returns the processed data.
3 collaborative systems.
- Networking supports multi user environments where interaction between users is fundamental to systems design
- Hence ensuring synchronisation between user actions over network is key
4 IoT in HCI
- Internet of things has expanded. HCI to include interactions between users and physical devices
- Reliable networking is critical for these systems to provide real time control and feedback.
Interaction models
In Human-Computer Interaction (HCI), interaction models describe the frameworks and paradigms that define how users interact with computers or digital systems. These models help designers understand user behavior and create more intuitive and efficient interfaces. Here are the main interaction models used in HCI:
1 Direct Manipulation Model
The direct manipulation model is one of the most intuitive and commonly used models in modern interfaces, especially for graphical user interfaces (GUIs).
- Characteristics: Users interact directly with objects on the screen using actions like dragging, clicking, resizing, or rotating. The feedback is immediate and visible, giving users the sense of control.
- Examples: Moving icons on a desktop, resizing windows, drawing in graphic design software.
- Advantages: Immediate feedback, easy learning curve, high user satisfaction.
- Challenges: Can become complex when dealing with abstract tasks or large datasets.
2 Menu Selection Model
In the menu selection model, users are presented with a series of choices or commands through menus, often hierarchical.
- Characteristics: Users select from a pre-defined set of commands or actions, typically organized in drop-down or pop-up menus.
- Examples: Traditional software menus (File, Edit, etc.), mobile app menus, contextual right-click menus.
- Advantages: Clear structure, easy to navigate for novice users, prevents user errors by limiting options.
- Challenges: Can be inefficient for expert users, cumbersome for repetitive actions or large tasks.
3 Form-Fill Interaction Model
This model involves users entering data into forms with fields for text, numbers, checkboxes, etc.
- Characteristics: Users provide structured input, often seen in data entry or online transactions.
- Examples: Registration forms, search engines, booking systems.
- Advantages: Easy to implement, structured data collection, works well with validation systems.
- Challenges: Can be tedious and time-consuming, prone to errors during data input.
4 Command-Line Interaction Model
In this model, users interact with the system by typing commands into a console or terminal.
- Characteristics: Requires users to memorize commands and syntax, offering more control and flexibility than GUI-based models.
- Examples: Unix/Linux command line, Git version control, SQL queries.
- Advantages: Powerful and flexible for expert users, can handle complex tasks quickly.
- Challenges: Steep learning curve, not user-friendly for beginners, prone to errors due to command syntax.
5 Conversational Interaction Model
In the conversational model, users interact with the system via natural language, either spoken or written.
- Characteristics: The system simulates a conversation with the user, interpreting user inputs in context to provide responses or perform tasks.
- Examples: Chatbots, virtual assistants (Siri, Alexa), customer service systems.
- Advantages: Natural and intuitive for users, hands-free interaction, applicable for users with low technical skills.
- Challenges: Natural language understanding can be imperfect, limitations in interpreting complex requests, and ensuring context continuity.
6 Gestural Interaction Model
This model is based on interpreting user gestures for controlling devices, often seen in touch-based and motion-sensing interfaces.
- Characteristics: Users perform physical gestures, such as swiping, pinching, or waving, to interact with the system.
- Examples: Touchscreen gestures (swipe to unlock), motion-based gaming consoles (like Kinect), VR hand controllers.
- Advantages: Intuitive for many physical interactions, highly engaging for users.
- Challenges: Limited precision, physical strain for repetitive use, may require learning unfamiliar gestures.
7 Model-View-Controller (MVC) Model
MVC is an interaction model commonly used in software development, particularly for web applications.
- Characteristics: Divides the system into three parts: the model (data), view (user interface), and controller (logic). The model updates the view whenever data changes, and the controller mediates user inputs to update the model.
- Examples: Web applications, enterprise software systems.
- Advantages: Clear separation of concerns, easy maintenance and scalability.
- Challenges: Can be complex to design and implement, requiring proper coordination between components.
8 Agent-Based Interaction Model
This model introduces software agents that act on behalf of the user, often autonomously performing tasks based on user preferences.
- Characteristics: Agents learn from user behavior or follow predefined rules to make decisions, reducing the need for direct user input.
- Examples: Recommender systems (Netflix, Amazon), intelligent personal assistants.
- Advantages: Reduced user effort, anticipates user needs, time-saving.
- Challenges: Loss of control for the user, potential for mistakes, privacy concerns.
9 Multimodal Interaction Model
Multimodal interaction involves the use of multiple input methods simultaneously, such as speech, touch, gestures, or eye movements.
- Characteristics: Users interact with the system using a combination of different input types, allowing flexibility and adaptability in different contexts.
- Examples: VR/AR systems, smart home interfaces combining voice and gesture control.
- Advantages: Flexible, adaptive, natural user interaction, can be more accessible for people with disabilities.
- Challenges: Complexity in design, requires robust system integration, potential for input conflicts.
10 Collaborative Interaction Model
This model focuses on interactions where multiple users collaborate through the system, often in real-time.
- Characteristics: Supports multi-user environments, where the system mediates interactions between users, often for shared tasks or communication.
- Examples: Online collaborative tools (Google Docs), multiplayer games, virtual whiteboards.
- Advantages: Promotes teamwork and coordination, enables real-time collaboration.
- Challenges: Synchronization issues, managing conflicts in shared workspaces, scalability.
Conclusion
These interaction models provide frameworks for designing user interfaces and interactions. Each model has strengths suited to different contexts, and designers often choose models based on the target user base, the complexity of the tasks, and the type of interaction required. Many systems combine elements from multiple models to create richer user experiences.
Interaction framework
In HCI interaction framework provides a structure to it to understand and design the interaction between users and computers. It breaks down the process of interaction into distant components, helping designers evaluate and improve the user experiences.
The most commonly used one is Norman’s model of interaction.
Norman’s model of interaction
Developed by Donald Norman which describes the stages that user undergo through the interacting with the system or product emphasising the cognitive and behavioural process involved.
Key components:
Execution phase
Forming the goal,
forming the intention,
Specifying action executing the action evaluation phase
Perceiving the system state,
interpreting the system state
evaluating the outcome
Model emphasises two gaps in interaction:
1 Gulf of Execution
The gap between users expectation and systems ability to support those actions.
2 Gulf of evaluation.
The gap between systems feedback and users ability to understand or interpret it
adv:
1 Improves user experience by understanding points of confusion and frustration
2 Highlights the importance of closing the gulf of execution and evaluation, making the system more intuitive and effective
Ergonomics
“C:\Users\mural\OneDrive\Desktop\BSCS\3rd year\6th sem\HCI\1. unit\Interaction.docx”
Ergonomics in HCI refers to the science of designing interactions, workspaces and tools to optimise human comfort, efficiency and safety during the use of computer systems.
The goal of ergonomics is to ensure that systems are designed in a way that minimises physical strain fatigue and discomfort while maximising user performance, satisfaction and well being
key aspects:
1 Physical economics
Deals with physical interaction between user and their computer systems, including hardware(Keyboards mouse monitors) and their environment(Seating lighting)
2 cognitive ergonomics
Deals with well supported cognitive processes like memory decision making and attention. Ensuring that the information is displayed in clear and organised manner
3 visual ergonomics
How design of displays and environments affect the visual comfort? Like monitor positioning screen glare font size and colour contrast.
4 audit ergonomics
Involves use of sound in systems and how audio feedback is perceived by users like auditory feedback noise reduction
5 temporal ergonomics
Addresses the impact of time related factors such as how long uses interact with the system and frequency of tasks
6 haptical economics.
Focuses on touch based interaction and the design of input devices that provide tactile feedback Call haptic feedback and pleasure sensitivity
ergonomic guidelines for HCI design:
1 Design for natural posture
2 reduce repetitive motions
3 design for multiple body types.
4 Provide immediate and clear feedback
5 use legible fonts and visual elements
6 minimise glare and ensure proper lighting.
Importance of ergonomics in HCI
1 Increases user comfort
2 Increased productivity
3 Reduced errors
4 inc user satisfaction.
Interaction styles
“C:\Users\mural\OneDrive\Desktop\BSCS\3rd year\6th sem\HCI\1. unit\Interaction.docx”
They play crucial role in determining effectiveness efficiency and satisfaction of user experience.
1 Commandline interfaces (CLI) 4
Kioser’s input commands via text in terminal or command prompt This style is less graphical and involves precise, often complex textual input
eg: Unix/Linux terminals, windows command prompt.
2 graphical user interface (gui)
Provides a very rich interaction style where uses interact with the elements like Windows icons, buttons and menus using pointer devices such as mouse and touch
eg: Ms windows, mac os, web browsers
3 menu driven interfaces
Users can interact by selecting options from a set of predefined menus or lists
eg: Atm interfaces, drop down menus in applications
4 form fill interfaces
User input data by filling out feilds in structured form.
eg: Online registration forms, data input forms
5 direct manipulation interfaces
User interact with objects directly on screen, such as dragging files to folder or resizing windows by dragging edges
eg: Desktop environments photo editing software file explorer.
6 Natural language interfaces
Users can interact with the system using spoken or written. Natural language allowing for conversational interaction
eg: Voice assistants(siri, alexa), Chadbots
7 touch and gesture based interfaces
Interaction occurs through touch screens or gesture recognition systems, often with multi touch capabilities or motion sensor
eg: Smartphone tablets gaming consoles
8 Virtual reality (VR) and augmented reality(AR) interfaces
Users engage with immersive environments through vr headsets or interact with digital objects in real world via AR
eg: Oculus rift VR Microsoft Hololens Ar
9 Multimodal interfaces interfaces
Combines multiple interaction styles like voice gesture, touch to allow users interact with the system in various ways
eg: Smart homes ARVR Environment with both Voice in Gesture input.
