IT 223 (Part 5)

• Learnability is all about how easy it is for someone new to start using something (like an app or a website) and get really good at it quickly.
• If you pick up a new video game, learnability is how quickly you can understand the controls, figure out how to move around, and start having fun or winning.
• A system with high learnability means you don't need a lot of time or a thick manual to get going; you can jump right in and feel like a pro sooner rather than later.
• Predictability: Determining effect of future actions based on past interaction history
• Predictability: Clearly shows what your actions will do.
• Predictability: If you press "play" on a music app, you expect it to start playing music, because that's what happened in other apps.
• Predictability: Seeing a trash bin icon and knowing clicking it will delete something.
• Synthesizability: A design feature that provides support for the user to assess the effect of past operations on the current state.
• An example of synthesizability in learnability is the "undo" feature found in many software applications.
• Synthesizability refers to the ability of users to assess the impact of their past operations on the current state of the system.
• Familiarity: Measure how prior knowledge and experience of the user can be applied during interaction with a new system.
• Familiarity in the context of human-computer interaction (HCI) refers to the ease with which users can apply their previous knowledge and experience to interact with a new system.
• A system with high familiarity is intuitive for users because it behaves in ways they expect based on their past experiences.
• Guessability: This is about how well the design meets the user's initial expectations.
• For instance, a play button (triangle shape) on a video player is guessable because most people expect it to start the video.
• Use of metaphors: Refers to using real-world analogies in design, like a desktop icon representing the main screen of a computer, helping users intuitively grasp how to navigate the interface.
• Affordance: Indicates how the design elements suggest their function, such as a scrollbar looking like something you can drag up or down to view more content on the page.
• Generalizability is extending specific interaction knowledge to new situations.
• Generalizability refers to the ability of users to apply knowledge gained from one context to another within the same system or interface.
• Generalizability is about how learning one part of the system helps to understand and use other parts.
• Generalizability: If a user learns to cut and paste text in a word processor like Microsoft Word, they should find it easy to apply the same action (cut and paste) in other applications, such as an email client or a graphic design tool.
• Generalizability: This concept relies on consistent interaction patterns across different areas of the system, enhancing the user's ability to generalize their knowledge and skills to new tasks within the system.
• Consistency is the likeness in input-output behavior arising from similar situations or similar task objectives.
• Consistency means that a system should behave in a uniform way across its various parts.
• When actions are consistent, users can transfer their knowledge from one part of the system to another.
• Consistency: For example, if double-clicking an icon on a desktop opens an application, then double-clicking should open items similarly in other contexts within the operating system.
• This consistency helps users learn the system faster because they can

  predict how it will respond to their actions based on their past experiences.
• Flexibility means the multiplicity of ways in which the end-user and the system exchange the information.
• Flexibility in human-computer interaction refers to the system's ability to adapt to the user's needs, allowing for multiple ways to achieve tasks or goals.
• Flexibility: It encompasses the ease with which users can customize or modify the system to better suit their preferences and the way they work.
• Multithreading: Enables users to perform multiple tasks simultaneously.
• Multithreading: For instance, in a web browser, users can open several tabs to work on different websites at the same time.
• Multithreading: In a web browser, you can download a file, watch a video, and chat in a messenger app all at the same time within separate tabs.
• Task Migratability: Facilitates the transfer of tasks across devices or systems, providing continuity in the user experience.
• Task migratability is the ability to pass a control for the execution of a given task so that it becomes either internalized by the user or the system or shared between them.
• Task Migratability: Using a smartphone to listen to music while browsing the internet and receiving notifications. This shows how users can engage in different activities simultaneously on the same device.
• Task Substitutivity: Offers alternative methods to accomplish tasks, catering to different user habits or situations.
• Substitutivity is allowing equivalent values of input and output to be arbitrarily substituted for each other.
• Task Substitutivity: In a word processor, selecting text can be done by mouse dragging, using shift-key with arrow keys, or tapping on a touchscreen. This variety allows users to choose their preferred method.
• Customizability is the modifiability of the user interface by the user or the system.