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Introduction to HCI

This chapter introduces the term Human-Computer Interaction (HCI), its historical background, and the differences between “interface” and “interaction.” It also discusses the related fields and the types of professionals involved in the HCI field.

1. Associated Terms and Their History

HCI, or Human-Computer Interaction, originates from the term “Human-Computer Interface” in English. There’s confusion between “interface” and “interaction” due to historical uses of the term “interface.” While the term “interface” was coined around 1880, it gained wider use in the 1960s when it started being applied in the computer industry. Initially, the scientific community rejected it, arguing that it carried jargon-like connotations, suggesting alternatives such as “cooperation” or “interaction,” which were ultimately rejected. The term “interface” eventually became widely accepted in the 1970s, signifying the interaction point between a computer and other entities, like printers or human operators.

The term “interaction” is broader, encompassing new fields of study involving communication between users and computers or other products. “Interface” specifically refers to the point of interaction, such as input and output data languages, as well as interaction protocols.

As computers became more complex, the field expanded, leading to the emergence of HCI as a more comprehensive term in the 1980s. HCI not only focuses on interface design but also on the interactions between users and computers. HCI involves designing, evaluating, and implementing interactive systems for human use and studying relevant phenomena related to interaction.

Evolution of HCI

The evolution of HCI is marked by different technological milestones:

  • 1950s: Hardware interfaces for engineers with various buttons.
  • 1960s-1970s: Programming interfaces (e.g., COBOL, FORTRAN).
  • 1970s-1990s: Terminal interfaces with command languages.
  • 1980s: Interactive interfaces for dialogue, such as Graphical User Interfaces (GUIs) and multimedia.
  • 1990s: Interfaces for collaborative work (networks and groups).
  • 2000s onwards: Interfaces become ubiquitous with mobile devices, interactive screens, and embedded technologies everywhere.

The design of interaction is crucial for the success or failure of a product or company. The usability of interactive products greatly impacts brand perception, user satisfaction, and customer loyalty. For example, poor usability can lead to product abandonment, as seen with search engines like Alta Vista, which were replaced by more effective solutions like Google.

As the demand for usable products grew, the number of professionals in the interaction design field increased. This multidisciplinary field now involves professionals from sociology, anthropology, and drama, although this can lead to communication challenges. Despite these issues, the result is a greater focus on the user.

2. Interaction Design as a Growing Business

At one point in history, it was concluded that “interaction” is a broader concept than “interface.” Imagine a large set called interaction, which requires an element to enable communication—the interface. Understanding interaction makes it easier to design the interface. The interface stimulates interaction, allowing the user to receive responses related to their tasks. It functions as both an input device and a means of delivering responses to the user. For every action, a new response is expected from both sides: the system and the user.

The user interface in a computational system is the complete set of elements that makes the interaction process explicit, including input and output devices, the information presented or sent by the user, the system’s responses, system behavior, and user actions. Interface components enable communication between users and devices, facilitating data input and output processes. These components can be virtual, like checkboxes or buttons, or physical, like a mouse or keyboard.

Interaction refers to the exchange between users and equipment, such as computational systems, occurring through basic tasks. Various interaction styles can enrich communication, though customizing interaction processes can also increase complexity. For experienced users, flexible configurations may enhance the interaction.

Some suggest the concept of interaction originated in physics, later integrated into sociology and psychology, and eventually applied to computing, becoming “interactivity.” Interaction can also refer to communication between people mediated by systems like chat or forums. However, this material focuses on human-machine interaction and its design conditions.

Metaphors and Mental Models

The ease of communication in the interaction process depends on metaphors and mental models, which are concepts acquired by users. Metaphors are analogies used in interaction design, suggesting relationships between known objects or processes. In virtual reality systems, metaphors help define realism. For example, presenting content within familiar scenarios makes it easier for users to understand interface components. Mental models are assumptions people create based on past experiences, even if the imagined procedure isn’t the most suitable.

Interaction Resources

The many interaction resources allow for diverse combinations of interfaces and actions. Keyboards, monitors, virtual elements, among others, motivate various types of research. The Graphical User Interface (GUI) offers solutions for the use of graphical elements such as menus, windows, palettes, icons, etc. Research on the design of technological products involves concepts of ergonomics, which suggest human capabilities for using physical interfaces, as well as design processes, testing, and more. In the 1980s and 1990s, new resources emerged, and the market for multidisciplinary research expanded with discoveries in interactive interfaces such as voice recognition, multimedia, virtual reality, learning environments (training and education), and wireless networks.

3. Interfaces and Interaction Design

Interaction design involves creating solutions to enable dialogue between users and systems, whether a device or software. The interface, one of the key elements of this process, can be divided into two categories of communication:

Physical Interface (or hardware): Refers to physical means of contact, such as cables, wires, mice, and keyboards. These components are responsible for enabling the tangible interaction of the user with the system.

Logical Interface (or software): Refers to the cognitive interface, based on aspects such as lexical (functional), syntactic (structural), and semantic (content). Examples include GUIs (Graphical User Interfaces) and communications between software and hardware.

The reason for having two interfaces is that many devices rely on the combination of the physical interface and graphical elements of a logical interface. These graphical elements make up the graphical interface, which facilitates user interaction with the system or application.

For the vast majority of people, the mouse and keyboard are important parts of the interaction process – they are examples of physical interfaces. The absence of a mouse can leave anyone panicked, even an experienced user. Using programs to edit images, text, or even the process of turning off the computer are activities that are rarely done without a mouse. Then you might say, “But it’s possible to do these tasks using only the keyboard!” Indeed, the flexibility of the operating system or applications allows the user to have more than one type of access or interaction format for many activities on the computer – these are shortcuts.

The logical interface is better known for its graphics and the rules determined by GUIs (Graphical User Interface). This type of interface is part of virtually every new technological device on the market, and we will likely coexist with them for a long time. New technologies tend to minimize the use of physical interfaces for communication, as seen in touchscreen devices. However, the physical interface can still be identified. The screen, the user’s finger, a mouse button, or a stylus, for example, are means of establishing contact for data input. The graphical screen and speakers communicate task completion.

The combination of physical and graphical or logical interfaces in mobile phones requires an interaction design that considers a comprehensible relationship between the device’s application and its buttons and keyboard. In evaluations conducted by students in the TASI course using design principles, usability goals, heuristics, and other concepts, it was found that the Nokia device is one of the simplest to operate, while the Motorola is among the most complicated.

Developing high-quality interfaces can consume nearly 50% of the time and resources allocated to the project (Filho, 2005). The degree of difficulty in implementing good designs can increase as the number of interaction formats and elements involved in the project grows.

Interface Consistency

With the evolution of technology through scientific studies pointing to new interface and interaction solutions, new products are starting to combine physical and graphical interfaces. A well-known example is the computer, with applications that work with graphical output (monitor) and sound output (speakers), alongside devices like mouses, keyboards, and joysticks. Mobile phones also provide graphical output on the screen and sound, typically manipulated through physical interfaces such as alphanumeric keypads and various buttons. Other machines, like vending machines and ticket machines, feature control panels with buttons and instructional screens.

What is important to understand about combining interfaces is the relationship between graphical and physical elements, which needs to be effective, clear, and consistent so that, through physical devices or interfaces, the graphical interface responds according to user expectations. In short, anything designed must consider the following aspects:

  • Address the type of activity expected by the user.
  • Study the most appropriate interface for data input and output.
  • Offer complementary features to make the interaction process more flexible.

The most common and well-known interface elements that allow interaction in computational systems are menus, commands, forms, icons, buttons, and combinations of physical devices.

Related Fields in HCI This knowledge area is defined by its multidisciplinary nature, involving experts and professionals from various fields, such as:

  • Psychology
  • Sociology
  • Anthropology
  • Information Systems
  • Computer Science
  • Graphic Design
  • Ergonomics

Why this matters? Given that early computer systems were developed by hardware engineers, what kind of experience could they have had regarding human conditions such as abilities and limitations to use the first systems they created? How would the process of interaction be perceived by the user?

With the advent of the monitor in the 1970s, professionals curious about technological innovations began seeking solutions for tasks involving human cognition. This sparked collaboration between computer scientists and psychologists. Following this, new challenges led to the development of further solutions.

As a result, the profession of the interaction designer emerged, challenging new technologies in search of solutions for the user. The interaction designer is now responsible for generating ideas that provide maximum comfort to the user during interaction activities.

4 The Interaction Designer

To better understand the role of the professional responsible for creating interaction designs, it’s interesting to use the analogy proposed by Preece (2005), which suggests a contrast between different areas.

Professional Role Correlation: The software engineer is to the civil engineer, as the architect is to the interaction designer.

The architect’s concern in their projects is with the person who will use the built space, ensuring comfort for living or working, designing adequate circulation, windows that allow natural light and ventilation… in summary: Concern for the user of the Building or System!

The civil engineer’s concern in their projects is to ensure the structure is strong enough to support people, equipment, and weather conditions… in summary: Concern for the Building or Code!

The software engineer is concerned with creating robust solutions for the systems they design and develop. In summary: Concern for the Building or Code!

The interaction designer is concerned with the process of using the system and the performance of the activities carried out by the user. In summary: Concern for the user of the Building or System!

Professions Arising from HCI (Human-Computer Interaction)

This field has led to the emergence of several new professionals who are trying to establish themselves in a market still in development or definition, striving to keep up with a field that is still in the process of establishing activities and competencies. Among them, the following professionals stand out with their activities:

  • User-Centered Design Analyst: This professional conducts the initial interviews with users and clients, identifying their needs and transforming them into system requirements.
  • Information Architect: Works with analysts or immediately after the requirements gathering phase to understand the business rules and structure the necessary information. Based on the requirements, they define processes for organizing, structuring, and distributing information and activities in a way that can be easily understood by users. They may also develop wireframes for identifying spaces allocated for content blocks and work on webwriting, defining clear and objective labels.
  • Web Designer: Builds on the work of the information architect, creating the visual elements from wireframes and mockups. They define details like font types and sizes, color palettes, logos, and icons. The web designer may also restructure the placement of interface components if needed and makes decisions about the presentation of information, especially when user interaction needs to stimulate the senses (such as the way links are presented).
  • Usability Specialist: This professional has expertise in concepts and tools for analyzing systems that need improvements, evaluating prototypes, and reviewing competing products to identify strengths and weaknesses. They perform heuristic evaluations and provide recommendations to improve usability.
  • Tester/Evaluator: The testing professional has knowledge of processes that help in evaluating systems during production, identifying issues like logic errors, implementation issues, and cosmetic problems. They document results in reports and use them throughout the testing process. They also plan other types of evaluations using representative users, a task which can also be managed by the usability specialist. Testers are familiar with techniques and processes for evaluation during various stages of development.

There are many other roles and job titles in this area, and some professionals are more in demand or “utilized” than others. Some roles are so specific that they would rarely be hired as part of a development team. However, the usability professional, due to the growing recognition of their role, is attracting the attention of project managers who hire them for development teams. This demand stems from the market and users’ increasing expectations. Even though these professionals have specialized tasks, in some teams, they may take on a variety of activities.

5. Activities

Discussion: Interaction Procedures for a Wrist Cellphone

Team of three people:

  • How would the interaction procedures work for a wrist cellphone? What would be the difficulties, advantages, modes of interaction, and usage if only one hand could be used?

Research:

  • Investigate other professionals in the fields of IHC, usability, AI, Design, and related areas.
  • How did the field of IHC emerge, and who are the key figures (professionals and related areas) involved in its establishment?
  • Define the role of the interaction designer and their relationship with the software engineer. What analogy can be drawn with civil engineering and architecture?
  • What are the differences between interface and interaction?
  • What types of interfaces can be identified in devices that allow interaction?
  • What current professionals can be identified as a result of IHC demands?
  • What are logical interfaces and physical interfaces?