User - Centered Design (UCD)

“User-centered design (UCD) is a design philosophy where the end-user’s needs, wants and limitations are a focus at all stages within the design process and development life cycle”.


User-centered design (UCD) is a flexible process for software development projects that enables teams to more effectively meet the needs of users and customers.

The UCD process defines a series of collaborative activities that involves the entire product team, ideally including:

• Developers
• Solution managers
• Interaction designers
• User researchers
• Other key stakeholders

These collaborative activities take place in five distinct phases: Plan, Research, Design, Adapt, and Measure.

Keep in mind that the UCD process is flexible. If no interaction designer or user researcher can be assigned to a project, then the UCD activities can also be performed by solution managers and developers with the appropriate training. If some steps in the UCD process are not feasible, they can be left out. Clearly, the closer a development team sticks to the entire process, the better the results will be. But in the end, any UCD activity is better than none! Sometimes even small design activities can bring big rewards.

Human Computer Interaction (HCI)

What Is Human Computer Interaction?

“Human–computer interaction (HCI) is the study of interaction between people (users) and computers”.

HCI (Human-Computer Interaction) is the study of how people interact with computers and to what extent computers are or are not developed for successful interaction with human beings. A significant number of major corporations and academic institutions now study HCI. Historically and with some exceptions, computer system developers have not paid much attention to computer ease-of-use. Many computer users today would argue that computer makers are still not paying enough attention to making their products "user-friendly." However, computer system developers might argue that computers are extremely complex products to design and make and that the demand for the services that computers can provide has always out driven the demand for ease-of-use.

One important HCI factor is that different users form different conceptions or mental models about their interactions and have different ways of learning and keeping knowledge and skills (different "cognitive styles" as in, for example, "left-brained" and "right-brained" people). In addition, cultural and national differences play a part. Another consideration in studying or designing HCI is that user interface technology changes rapidly, offering new interaction possibilities to which previous research findings may not apply. Finally, user preferences change as they gradually master new interfaces.

Interaction Design (ID)

What Is Interaction Design?

"Interaction Design is about shaping digital things for people’s uses."

It’s a tricky term this, one that doesn’t often get debated, being generally described as “designing the interactiveness of things”. Well, that’s simply not good enough. Everything interacts. Chemists creating explosives aren’t doing “interaction design”, but that doesn’t mean their things aren’t interacting. Quite the contrary. At CIID we’re always trying to get a more firm understanding of what we as interaction designers should be doing and what we in fact are doing. So this little essay (very short) is just an attempt to make a short definition of interaction design. It’s probably a hopeless task, but it’s an interesting thought experiment.

Interaction design is the idea of designing a system, and particularly (often exclusively) the user-facing parts of a system, that helps a user perform a task. The system can be screen-based, tangible, control-interface based, or any combination of the three and can be used for specific tasks or general ones. Generally the artifacts of that service or action have aesthetics and decisions that dictate elements of the communication between the user and the system.