Human Interface Guidelines/The Laptop Experience/The Journal
The Notion of "Keeping"
The traditional "open" and "save" model commonly used for files will fade into abstraction on the laptops, and with it the customary floppy disk icon, as not only will the laptops not have floppy drives, but most likely the children will never see one of these largely obsolete devices. Instead, a much more general notion of what it means to want to keep things prevails. Generally speaking, we keep things that we want to hold on to, and the rest just fades with time. Appropriately, the Journal's primary function as a time based view of the activities a child has done and the objects she's kept reinforces this idea.
Most of us recognize the "save early, save often" mantra; most of us have failed to live it and incurred the consequences. The laptops aim to eliminate constant concern for this type of technicality, making automatic and incremental backups and allowing the children to focus on the activity itself. These incremental backups will occur at regular time intervals, and activity events such as changes in scope, new participants, among others can trigger them as well. In order to cater to the needs of many types of editing environments, activities can also specify "keep-hints" which prompt the system to keep a copy. For instance, a drawing activity may trigger a keep-hint before executing an "erase" operation immediately preceded by a "select all". Of course, a child herself may choose to invoke a keep-hint by selecting the "keep in journal" button, but adequate adoption of this new notion of keeping from activities should virtually eliminate need for this.
Based on the Object model associated with files, each kept Object is, technically speaking, a separate instance of the activity which created it. This eliminates the need to "open" a file from within an activity, replacing the act of opening with the act of resuming a previous activity instance. Of course, a child will have the option to resume a drawing with a different set of brushes, or resume an essay with a different pen, providing "open with" style functionality, but no substitute for an "open" command will exist within an activity's interface.
Along with the idea of implicit keeping, the laptops will drastically minimize the hierarchical filesystem as a means for organization, replacing it with a temporally organized list of activities and events, furthering the Journal metaphor. This drastically simplifies the auto-keeping behavior, since it eliminates the need to specify a location in which a newly started activity should be kept; naturally, the newly started activity will appear as the most recent entry in the journal.
Temporal organization functions naturally in the absence of explicit or hierarchical methods, since humankind's intrinsic relationship to time gives them, at the very least, a relative notion of "how long ago" something happened. By moving back through the Journal, a child can simply locate the period in time within which she knows she made something, and then employ additional use of searching, filtering, and sorting to pinpoint exactly what she's looking for.
Due to the laptops' limitations in storage capacity, the potential exists for the Journal to contain so many entries that no more may be written. However, the frequency of such occurrences is limited by temporal falloff, which tidies up the Journal contents and keeps space available for new entries. One might think of this as an intelligent combination of garbage collection and disk defragmentation.
The driving principle here is that of temporal granularity, derived directly from our very capacity for human memory. Our minds, generally speaking, maintain a high level of granularity with respect to very recent events, but only a low granularity for events from several years ago. Moreover, this granularity tends to follow a logarithmic curve, where the past few minutes remain quite clear, the past few hours more blurry, and by last month quite vague. When we look years into the past, only specifically memorable events stand out in our minds.
On the laptops the policies are a bit more strict, but the principle remains the same. With a finite amount of memory, some means of managing what's remembered, or kept, and what's forgotten, or erased must exist. An intelligent algorithm will assist children in identifying "forgotten" entries. Taking into account how old an entry is, how many times she's viewed it, how recently she's worked on it, how many hours she's worked on it, how many people she's worked on it with, its tags, and even more forms of automatically generated metadata, the Journal can suggest to her those entries which it feels can be erased. She will then have the opportunity to review those items prior to their erasure, if she wishes, and can keep any she still feels attached to.
In a time where gigabytes have become cheap, many of us still manage to fill our hard drives. Excepting the cases of multimedia collections of audio or video files, much of that space is consumed by files we either don't remember we ever made, or will never open again. On the laptops, where space is precious, so too will be the objects and entries that remain in the journal years down the road. The temporary, the experimental, the duplicate, and the unwanted files will naturally fall off the bottom, maintaining a browsable history of those that remain important to the children.
The Power of Metadata
Implicit & explicit
Powerful Search, Filter & Sort
Special filters, labels or tags: about to be removed, lazy deleted (trash can), in progress...
Implicit Versioning System
Automatic, incremental saves...
Viewing revision history...
Automatic Backup and Restore
Automatic backups to server...
Full restore (temporal)...
Partial restore(by object)...
The Journal as a Progress Indicator
Two stages for entries...