Changes

Incremental backups occur regularly and are also triggered by such activity events as changes in scope, new participants, etc.  To cater to the many needs of the editing environment, 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 may choose to invoke a keep-hint by selecting the "keep in journal" button<!--[{{fullurl:olpc:File:542-keepicon.png}} http://wiki.laptop.org/images/3/32/542-keepicon.png]-->, but the increasing adoption of this new concept of keeping should ultimately eliminate this.  

Incremental backups occur regularly and are also triggered by such activity events as changes in scope, new participants, etc.  To cater to the many needs of the editing environment, 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 may choose to invoke a keep-hint by selecting the "keep in journal" button<!--[{{fullurl:olpc:File:542-keepicon.png}} http://wiki.laptop.org/images/3/32/542-keepicon.png]-->, but the increasing adoption of this new concept of keeping should ultimately eliminate this.  

Based on the Object model associated with files, each kept Object is, technically speaking, a separate instance of the activity that created it.  This eliminates the need "to open" a file from within an application, and replaces 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" a different tool kit style of functionality, but no substitute for an "open" command will exist within an activity's interface.

Based on the Object model associated with files, each kept Object is, technically speaking, a separate instance of the activity that created it.  This eliminates the need "to open" a file from within an application, and replaces 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, and will so be provided with an "open with" (a different tool kit)-style of functionality; but, no substitute for an "open" command will exist within an activity's interface.

====Deprecating Hierarchy====

====Deprecating Hierarchy====