As far as I can tell, I just coined this word. A simple google search seems to agree with me. Interactive density is the number of possible ways to interact with an application at any given moment divided by the area used to display the UI. For all of these measurements let us assume you are using a display running at 1152×864 on a 15″ display (12″x9″). If every pixel on your screen did something different it would be an interactive density of 10,000 (interactive points per square inch). If you have a single button on your display then it would be 0.009.

Let’s look at the values for a few common cases:

• Photoshop: 1.11
• Word: 0.84
• Andalib Organizer: 0.28
• Google homepage: 0.16

It would be interesting to do a study to see if there is a strong correlation between interactive density and the percentage of the population that can figure how to perform tasks using a given UI.

I think that this provides an interesting way to analyzing UI and hopefully will provide insight into the appropriate level in interactivity to provide in the UI to solve certain problems.

Andalib products are designed to be distinctive and intuitive. This is a challenging task involving a balance between new design ideas and potential of user confusion. The Organizer product contained an innovative method for selecting the date to view; we call it the Date Slider. It is a combination of 3 selectors, a selector being a control designed to allow the user to pick or select. Combobox, dropdowns, tab controls and radio buttons are all selectors. When choosing a selector you need to decide if the values are fixed or infinite, the numbers of values to pick from, the importance of the value, and how quickly you want to change the value. Combobox has a dropdown with a list of fixed values plus it lets you type in a new value, which makes it a good option for lists of infinite values with a few commonly used values. Tab controls and radio buttons present every choice at the top level, which make them good for important values that need to be quick to access. In the case of the Date Slider the value is important and the range of values is fairly limited. Plus the values have an inherent order, January precedes February. We came up with the idea of presenting them group into year, month and day in vertical sliders. It provided a very distinctive design element without much confusion. What do you think? Did we make the right call? Do you like it?

As a thought experiment I am pondering whether or not our daily interactions with our computers can be considered a form of communication, a language. We can consider buttons to be verbs, data and files to be objects, the cursor is the pronoun “I”, and attributes on files or other data are adjectives. That would seem to provide sufficient building blocks for constructing a language. You can take the analogy a little further and look at the grammar, ordering of the basic components of this language to provide meaning. Take the simple example of making text bold. You select the text then press the “bold” button. You could think of it as this sentence, “I want to make bold text from word ‘Talking’ to word ‘computer’”. How does the computer respond to all of this communication? It can change the pixels on the screen, send data across the network, modify data on the hard drive, or print. I believe that provides more than sufficient means to respond to our communication. As with all thought experiments, the important question is whether or not we can use this method of thinking to further our understanding of the underlying topic.

Why do people think that Word is complicated? It is probably because there are a lot of buttons and options. If we use this computer language concept, then we could rephrase this statement to Word has too many verbs. But now the statement starts to feel absurd, does English have too many verbs. Clearly Word has fewer verbs than English, so the problem is not the number but the presentation of the verbs. You can think of communicating with Word like trying to talk to someone speaking another language and using a dictionary to find each every word used in your communication. If we want to overcome this problem we must remove or improve the “dictionary”. Many people have tried to enable actually speaking to computers, with very little success, so I am going to ponder the improvement of the “dictionary”. Let us take all of the verbs, objects, and adjectives of our “language” and put them in big database. For each verb and adjective define the criteria that allows it be used. Can I use the “bold” verb on a table? Now we can build a new version of Word where we can record which verbs are used most often, which ones are likely to be used during the same session as the other verbs, which verbs are likely to be used by which types of people, which verbs are likely to be used with which types of objects. With this data we could re-arrange the UI to most optimally present verbs to the user. We can show them in context menus, menus, toolbars, ribbons, sidebars, etc. We can also develop different versions of Word for different types of users. We could have a doctor version, student version, teacher version etc. This is similar to professional terms, or words specific to certain professions.

In conclusion, there is no conclusion just a bunch of ponderings. Please feel free to add comments explaining the futility of this thought experiment.