The consumer experience vs. the PC experience
When was the last time you had to use an Exit command on a car stereo to stop the CD player? The answer is probably "never". Consumer appliances, such as car stereos, are designed to allow the user to simply switch from feature to feature without giving a thought as to what's happening inside the product to make the switch happen. The consumer can store presets, CD titles, etc., without concern as to how the function happens. It's the duty of the appliance to handle internal housekeeping and to do whatever else is necessary to make the features of the product work.

On the other hand, consider some of the major elements a personal computer user must know about. The user must know that the personal computer has memory, what it is and how much it has. They must know that it has a mass storage device, what it is and how much storage it has. They must be responsible for saving their work to the mass storage device so they can retrieve it later. The user must also know how the mass storage is structured or organized, because it's the user's responsibility to choose an appropriate location for storing information. When the user runs out of memory or mass storage, they must know how to take corrective action to remedy the problem. It doesn't take much observation to see the stark contrast between the consumer appliance experience and the PC experience.

The quest for the consumer appliance PC experience
The Auto PC, like a Palm-sized PC or Palm device, can be characterized as a cross between a computer and a consumer appliance. The objective is to give the rich, expandable feature set of a PC, while at the same time not burdening the user with the need to know how the device performs its features internally. Achieving the consumer experience requires removing the responsibility for managing the systems resources from the user. The illustration I gave regarding the PC experience can be boiled down to the simple fact that the PC makes the user responsible for resource management.