To explain in full how I came to write this blog post would require me to describe the entire mental journey that lead here, and that is a long story. It has been over eight months since my last post, after all. At the end of this post I have included a list of loosely related books I have read, that I am in the process of reading, or that I want to read. I am hoping to post more along these lines in the future.

sign in, log out, log in, sign out

Assuming everyone knows what a metaphor is, I am going to jump right in. My interest in this particular metaphor started when I noticed inconsistencies in the use of sign in/out and log in/out. Let’s look at some examples:

Flickr

Check out the great flickr set of sign in forms shown in this screenshot.

Del.icio.us

Basecamp

This is my favorite. The sign in page uses “Sign in” on the form button, but everywhere else it says “Login.” The sign out link, shown below, says Log-out.

There are variations on capitalization of the letters, spacing, and even hyphenating. Although these are minor details (though still important, I would argue) they do highlight the lack of a consistent language. Let’s look at some of the important pieces of a standard website sign in system.

Sessions

We already know that a user, at least in this case, is a person. When a user signs or logs in to a website they are starting a new session. From the American Heritage Dictionary:

session: A period of time devoted to a specific activity…

And, since we are talking software design, from the Free Online Dictionary of Computing:

session: A lasting connection between a user (or user agent) and a peer, typically a server…

Both of these definitions (and more!) can be found here: http://dictionary.reference.com/browse/session.

Log in/out

At the end of the full definition for session from the computing dictionary there is a see all reference to login. From the American Heritage Dictionary, here is the definition for login:

login: The process of identifying oneself to a computer, usually by entering one’s username and password.

When a user logs in to a website, they are identifying themselves to the website, which in turn authenticates the user’s identity based on the credentials provided by the user. If the user is successfully authenticated, a session is started. When the user leaves the website, they are essentially logging out. This may be done through a log out link or an expiring cookie. There are, of course, variations on this, but for simplicities sake, we are going to use this basic model.

The terms log in and log out accurately describe the activity being performed by the application. The user’s actions are indeed being logged, but people don’t have a strong mental model for this activity. Let’s look at a more generic definition of log, From the American Heritage Dictionary:

log: A record, as of the performance of a machine or the progress of an undertaking

The key word here is record. One example is a person recording, or logging, the time they spend on client projects through out the day. A sample day from the log might look like this:

Project	Start	End
Project A	9:00 AM	10:45 AM
Project B	12:30 PM	4:00 PM
Project C	4:30 PM	7:00 PM

When a new project session starts the person logs the start time, and then when the session ends, the end time. While this is an activity that most people are familiar with, it is not something that people usually associate with an engaging experience. I don’t know about you, but when I think about the logs I have kept and do keep, most of them are “work” related. Time log, exercise log, mileage log. While valuable, not so much “fun,” and also not something the everyone does regularly. People do, however, regularly sign things.

Sign in/out

Let’s explore the sign in metaphor as an alternative to the log in metaphor. To contrast those last two definitions, here is what the American Heritage Dictionary includes as a phrasal verb for sign:

sign in: To record the arrival of another or oneself by signing a register.

We are going to use the example of a person signing in to a meeting. The person identifies themselves to the meeting organizers by signing their name on a sign in sheet. A meeting organizer may informally authenticate the person’s identity by monitoring the sign in sheet and using visual recognition. The meeting session has a beginning and an end, and when the meeting is over, the person is essentially signing out. “Over and out!” There are a number of examples you could apply this to, such as signing in to a health club, signing the guest-book at a wedding, or the attendance sheet in class.

One of the fun things about metaphors are that they open the door to so many possibilities. We can extend the sign in metaphor in a number of ways. Here are a few ideas:

• A person joins the website and becomes a member
• The person’s member identity that travels with them around the site is their member badge
• The website is a space that users can move around in (a topic for another blog post), and interact with other members
• The person can ask the website to “Remember me” (rather than “Keep me signed in” or similar)

Because the sign in metaphor pulls from social activities (whereas logging is often a solitary activity) it can be used to provide a welcoming environment for new users and create a sense of community among existing users.

The sign in metaphor, as opposed to the log in metaphor, is also potentially more universal. Let me explain. When you ask someone to imagine signing something, they immediately know what you are talking about. We sign our names all the time. You may be imagining signing your name right now. Perhaps a memory of the last check you signed, letter you wrote, or form you filled out. Not only is it easy to imagine signing something, the very fact that we imagine doing it says a lot about how we interact with the world (also another topic for further exploration). Now, ask someone to imaging logging something, and they will likely ask you, “log what?” Even if you give them an example, say the one I illustrated above, the variations in how people imagine this are likely to be wide. I may use a notebook and organize the pages by project, rather than by day.

The sign in metaphor uses people’s existing mental model of signing in without masking the activity that the application is performing. The log in metaphor, while familiar to more technically savvy users, is weak and does not create the kinds of opportunities that the sign in metaphor does.

Further Reading

• Where the Action Is: The Foundations of Embodied Interaction ( Powells | Amazon ) by Paul Dourish, 2004, MIT Press.
• Activity-Centered Design: An Ecological Approach to Designing Smart Tools and Usable Systems ( Powells | Amazon ) by Geri Gay and Helene Hembrooke, 2004, MIT Press.
• Designing with Blends: Conceptual Foundations of Human-Computer Interaction and Software Engineering ( Powells | Amazon ) by Manuel Imaz and David Benyon, 2007, MIT Press.
• The Way We Think: Conceptual Blending and the Mind’s Hidden Complexities ( Powells | Amazon ), by Gilles Fauconnier and Mark Turner, 2003, Basic Books.
• Philosophy in the Flesh: The Embodied Mind and its Challenge to Western Thought ( Powells | Amazon ) by George Lakoff and Mark Johnson, 1999, Harper Collins.

The next two books I don’t own… yet.

• Metaphors We Live By ( Powells | Amazon ) by George Lakoff and Mark Johnson, 1980, Chicago University Press.
• Acting with Technology: Activity Theory and Interaction Design ( Powells | Amazon ) by Victor Kaptelinin and Bonnie A. Nardi, 2006, MIT Press.

I have been looking for an excuse to try out Todd Warfel’s Task Analysis Grid for a couple of months now, but I never could quite figure out how I would use it. Something about it appealed to me, but it didn’t quite fit with our process. I realized that what I was attracted to was not so much the content, but rather the format and how it can be used as a communication tool.

Recently, Brian and I sat down and talked out the things that we liked about the grid and the things that we could do without. What really appealed to me was the ability to represent priority and dependency, in two dimensions. Also, the representation of various phases of the project, which allows us to easily document potential future features (without getting bogged down by details) and helps us keep the bigger picture in mind as we focus on the immediate needs of the project.

Let’s look at simple example project grid.

I have broken the project into two areas: Blog posts and blog posters. The posts themselves are a higher priority than users, so that section comes first. Also, people are dependent on posts. Without posts, people would have nothing to do, and so would not be all that valuable. Yet, without people, posts can still exist and still be valuable.

Within each section priority and dependency are represented in two ways, order and color. In this example I have used green for high priority (must haves), yellow for lower priority (nice to haves), and pink for future features (next release). Individual posts are the highest priority, so they come first. Categories are the second priority, and are somewhat dependent on posts (what good are categories if you have nothing to put in them?). Comments are a lower priority, meaning if we had to cut one feature from the list, comments would go first. They are second in the list because they are directly dependent on posts. In the second column, user profiles are a lower priority and dependent on accounts, but are not planned for this release.

Our real grid looks quite a bit different, as we include more detailed information about each piece. Brian and I also talked about a possible third dimension that represents our process. I have more thoughts on this, but will save those for another post. ;-)

Another tool I am itching to try out is Blink Interactive’s Objects & Actions Analysis.

I am a book slut, so today is easily one of my favorite days of the year. It’s the first (open to the public) day of the Multnomah County Friends of the Library Annual Book Sale. The pickings were slim this year, but I did find a dozen or so books to add to my growing library.

I lust after all sorts of books, as my interests are wide, but recently I have been bringing home any book related to creating space. Robby was lucky enough to find one such book at the sale today, Personal Space: The Behavioral Basis of Design, by Robert Sommer. I had to trade for it (I gave up up The HP Way and The Meme Machine), but it looks to be an interesting flip through. I stumbled across this fun little prediction of how technology will change our learning spaces, written more than 35 years ago.

”...it will soon be possible to arrange eight different television monitors around a table to enable students to view different programs on each monitor, all without wires. The communications system will be based on laser beams conveyed through carpeting or other floor surfaces. Teaching machines, talking typewriters, and computerized information storage-retrieval systems will affect school design¹...”

How do you think our learning spaces will have changed 35 years from now?