As yet another example of our iterative approach to processing information, Chandler provides users with the ability to slowly pin down events on the calendar over time, with the possibility that some events will simply never be assigned a specific date and time.

As part of our user research effort in the area of calendaring, we studied the way that people use paper-based calendars, desktop calendars, wall calendars, and day planners. We found that people often jot notes to remind themselves of things they needed to do in the vicinity of the month, week, day in which they were due or likely to be done. This kind of "fuzzy" assignation of dates was especially helpful for tasks that didn't have a particular due date like end-of-day May 3rd, 2005, but instead, simply needed to get done in some rough time frame.

Another use case for fuzzy dates was to allow people to schedule events slowly over time, to essentially allow people to "pencil in" appointments onto their calendar without having to know beforehand exactly when they were going to occur. Some examples might include:

• Some time this week, I should really have lunch with Joe.
• Some time today, I need to stop in downstairs and thank the neighbors for watering the plants.
• Some time next month, I really need to schedule a doctor's appointment.

In fact, we'd like to be able to support allowing people to simple create calendar events with no dates at all, where the event acts simply as a reminder to schedule an event.

This gives people a place to park their information somewhere "meaningful" to them, where they are likely to find it again, even if they don't have all the pieces in place yet.

It's a great example of how Chandler in general strives to lower the bar to dumping data out of your head, into a trusted system and part of lowering that bar is to allow people to enter data into the system, even if the data is fuzzy and imperfect. The other half of that of course is to also provide a system to help people keep track of all these little "loose ends" they've created to ensure that they're tied up and closed in a timely fashion.

For more on the design list about this topic, see: http://lists.osafoundation.org/pipermail/design/2005-November/003443.html

• Mimi talked with another designer about how she actually uses her paper calendar, then mocked up a digital version of the paper calendar. A sticky on the calendar might be an incompletely-scheduled event or a note about the day or a note about a scheduled event -- it might be up to the user what it means.
  

• Another possible instantiation. Note that the "clean up garage" event hasn't got a time scheduled yet:
  

• Brad Lauster mocked up a different look with transparent stickies.
  

• Alec Flett mocked up an event that begins at a known time but the creator isn't sure when it will end.:
  

• Brad Lauster emailed us an image of how one might block out time for a task/event for which the delivery time is known -- if it's an important deliverable, the user might not want to schedule anything just before the deliverable time.: