Understanding Interface Technology

The heart of any computer is its processor. For this processor to be capable of doing anything, it has to have data on which to operate. There are many ways in which data is moved into, out of, and within your Mac. Just to use a Mac, you do not need to understand the various technologies involved in data transfers. However, if you add enhancements to your machine?whether they are external peripherals or internal system upgrades?you do need to understand these technologies.

In this chapter, you will gain a fundamental understanding of the various input and output technologies your Mac uses to move data. This understanding will help you when the time comes to add devices or other improvements to your system.


The term interface refers to the location at which two devices are physically connected. The term also refers to the technology that particular interface uses. For example, when someone refers to devices that use a USB interface, this implies that a specific physical connector is used (a USB connector) over which data following the USB specification is communicated.

On your Mac, there are two general types of input and output interfaces: those with external interfaces (ports) and those whose interfaces are internal to the machine.


Obviously, the types of interfaces available depend on the model of Mac you are using and whether you have added components to it. This chapter focuses on modern Mac models, such as the Power Mac G5, Power Mac G4, PowerBook G4, and so on. Newer machines generally support newer and better technologies. For example, the Power Mac G5 offers faster interface technologies than the Power Mac G4 does. Similarly, newer models of machines of the same class also support faster technologies. For example, later models of the Power Mac G4 added support for FireWire 800, whereas earlier models do not support this. In this chapter, you will find information on the more common interfaces used on modern Macintosh computers, but this chapter is not intended to explain all the interfaces that can be used. To be familiar with the technologies your specific Mac supports, you should study the specifications included with it.

    Part I: Mac OS X: Exploring the Core
    Part III: Mac OS X: Living the Digital Life