C H A P T E R 1

Newton and Its Users

You can make your application consistent visually and behaviorally by incorporating standard Newton interface elements in it. Visual consistency helps people learn and then easily recognize the graphic language of the interface. For example, users learn to recognize a black diamond as the source of a pop-up list of choices. Behavioral consistency of the interface means people only have to learn once how to do things such as erasing and scrolling. Then they can explore new functions and applications using the skills they already have.

User Control

Allow users, not your application, to initiate and control actions. Keep actions simple and straightforward so users can easily understand and remember them. Provide ample opportunity to cancel operations before they begin, and wherever possible allow users to gracefully stop an operation that’s underway. Be careful about unleashing agents, experts, or wizards that will do things behind a user’s back.

Forgiveness

People make mistakes, so your program should make it easy for them to correct their mistakes. Let them use the Undo button to reverse their last action. People need to feel they can experiment without damaging the system or their data. Create safety nets for people so they feel comfortable learning and using your product.

Always advise people when they begin an operation that has potentially dire consequences. Display a warning and have the user confirm the operation before proceeding. This doesn’t mean you should have users confirm every action. Frequent warning messages suggest something is wrong with

the program design—obviate some of the warnings by making more actions reversible.

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Observe Basic Human Interface Principles

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Apple 2 manual User Control, Forgiveness
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2 specifications

The Apple II is a defining product in the history of personal computing, first introduced in 1977 by Apple Computer, Inc. Designed by Steve Wozniak, the Apple II was one of the first highly successful mass-produced microcomputer products and played a significant role in bringing personal computers into homes and schools.

One of the Apple II's standout features was its color graphics capability. It was one of the first personal computers to provide color output, thanks to its built-in video interface. The initial model supported a resolution of 280x192 pixels with a palette of 6 colors, which allowed for vibrant visuals that set it apart from contemporaries like the monochrome Altair 8800.

The Apple II was notable for its open architecture. This design allowed users to expand the computer's capabilities easily through a series of expansion slots. Users could add floppy disk drives, additional memory, and various peripheral devices, making the system highly adaptable to individual needs. This encouraged a thriving ecosystem of third-party hardware and software, which contributed to its popularity.

Another significant feature was its use of the 6502 microprocessor. This 8-bit CPU was not only affordable but also powerful for its time, allowing the Apple II to run various applications efficiently. Along with a built-in keyboard and an innovative plastic case that housed its components, the design was user-friendly and appealing.

The Apple II also introduced the concept of “bootable software” through the use of floppy disks. The disk operating system (DOS) allowed users to store and run multiple programs without having to reload software manually, providing a level of convenience that had not been widely available before. Key software like VisiCalc, the first spreadsheet program, helped boost sales, showcasing the Apple II's utility in business and education environments.

The computer was also well-known for its early adoption of BASIC programming language. Apple provided an operating system that supported Applesoft BASIC, which enabled users, including students, to write their programs, further fostering a community of developers.

In summary, the Apple II's color graphics, open architecture, powerful 6502 processor, innovative use of floppy disks, and support for BASIC programming made it a revolutionary product in its time. Its legacy laid the groundwork for future personal computers and established Apple as a leader in the burgeoning tech industry. The Apple II remains an iconic symbol of the early personal computing era, reflecting a generation's transition into a digitally connected world.
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