The amount and type of information plays a critical role in how much information to display. A good practice is to consider the type of user interface you are designing to set the information density or input controls on a screen. Information density driven UX gives designers and developers a guide to understand the user and the how an interface should be presented to the user.
We can categorize user interface types into two groups:
Operational interfaces are sometimes referred to as applications. These interfaces are used to allow a user to achieve one or more goals. Examples are email applications, CRMs, financial trading sites, and word processing software. These applications have multiple controls which a user interacts with to achieve one more outcomes. As the sophistication of the user increases, the information density should increase.
Informational interfaces are sometimes referred to as marketing sites or brochure-ware. They convey information to a reader. Examples are corporate landing pages, product sheets, infographics, and dashboards. Good design focuses on the user experience while targeting the goals of the business. The user interface needed will be different depending on the goals and the user.
For example a highly skilled user, such as a pilot, who performs the operational goal of flying a commercial passenger airliner requires a highly complex user interface. This user interface requires craft-specific training, ground school education, and thousands of hours of flight time. This takes years to master.
However, that same pilot when performing the operational task with drawing money from an ATM machine is faced with a different user interface. The ATM user interface must be usable by everyone with a myriad of languages and disability levels. ATM screens present few choices per screen allowing easy choices for users, unlike the pilot’s cockpit. It’s likely very few people have ever needed ATM operational training.
The amount of control the user should have needs to increase with their comfort level and the speed at which they are able to operate. This usually means the interface becoming more utilitarian focusing on goals and speed at the expense of aesthetics.
User interfaces should change when we want to convey information. The information density depends largely on the goal of the messenger. For a corporate or product marketing website, it becomes critical to quickly and clearly convey what the business or product does to benefit the customer. A reader is taking time to read the marketing material. In these cases, we need to convey the value to the customer in terms and language they will understand. Distraction and jargon should be kept to a bare minimum.
Another type of low density information interfaces are emergency dashboards. These are user interfaces which give statuses, warnings, and alerts. These have the same goal as the product website above. They need to quickly and clearly express the problem and the corrective action needed to be taken. Again, distractions should be kept to a minimum.
Other informational interfaces are less goal oriented. These are exploratory interfaces designed to present a broad array of information. Examples of these are infographics and exploratory dashboards. These are great ways to give the reader a general feel or overview of a proposed situation. In these cases, any call-to-action will likely be lost. The user will only be scanning for interesting tidbits of information rather than a goal seeking reader trying to make a purchasing decision.
Usually, the goal of a high-density informational interface is to make an elicit a reaction. Consider a corporate website to elicit confidence or an infographic to elicit fear. In these interfaces the content writer is attempting to make an impression. The goal of these impressions is to elicit a behavior change usually to make a purchasing decision sometime in the future. Excellent design is key to conveying the message and making the impression for the business. Since much of the information will be overlooked by the user, there should be a greater focus on the design and less on the content.
For operational interfaces, information density should increase as the user sophistication increases. Also, design becomes less important as functionality becomes asserts are larger role. Conversely, informational interfaces require less information density as the goal changes to convey a specific goal or message. Information density and focus on design should increase as the goal changes to elicit an emotional response or make an impression.