Lisa is a software developer. She decides to write an image editing program for the Savi operating system. She downloads the software developer kit and reads the manuals where she is told the following:
Programs are never stand alone. They can only be enhancements to the existing four panel interface.
There are no traditional menus or toolbars; items are first selected and then the properties panel reflects the current state of the item. Lisa's program would add the capability to adjust various properties of the selection. When writing the elements of her program, Lisa would list the performance requirements for each function. If the block was in the PDA which has less performance than the desktop, certain properties of the image selection may not be visible for editing.
Mac is a software developer as well. He wants to write a budgeting application. He would be required to create a new type of stationery for use in the document panel to represent deposit and withdrawal slips and the results or projections would show up in the database and timeline panels. His program could enhance the selection properties of any number or currency displayed, no matter what type of stationery it was sourced from.
Wherever possible, applications would pull data from that already in storage. So Mac's budgeting program would show banking details from Bob's existing bank account info, and get foreign currency rates from Bob's bank. There would only ever be one master object physically located in the block for each file or piece of information. All instances of each object would be pointers to the original so that if the original is changed then all instances would reflect the change; if Bob changed banks then that would be reflected everywhere.
If Bob decided to buy Mac and Lisa's programs then they would be purchased using Bob's bank via his block and downloaded to his block; he would not be able to transfer them to another block. If Bob sent some output from a purchased program to someone who didn't have the program required to view it then the recipient would be prompted to purchase the program using a form in the Properties panel, already including the recipient's banking details; a portion of the proceeds would be forwarded to Bob as a commission.