Absolute Beginners Guide to A+ Certification. Covers the Hardware and Operating Systems Exam

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Don't miss the Study Lab materials found on the CD accompanying this book. Each Study Lab is tailored to the individual chapters in this book, meaning that you'll quickly be able to determine which topics you understand well enough to pass the exam and which topics need more study. The Study Labs are presented in printable PDF format so that you can take them with you to study at work, on the road, or even in your car just before test time!

The Absolute Minimum

Here are the high points of this chapter. Review these just before you take the exam to brush up on the major topics and help you identify what you need to review.

  • The basic unit of measurement for storage or information management is the byte.

  • When stored as plain text, one character uses one byte of disk space.

  • Other file formats require more space than .TXT (plain text) files because they reserve space for formatting and document management information stored as part of the file.

  • Binary numbering uses two digits, 0 and 1. Binary is also called base 2.

  • Decimal (base 10) uses digits 0 “9.

  • Binary (base 2) uses digits 0 “1.

  • Hexadecimal (base 16) uses digits 0 “9 and A “F.

  • Decimal numbers can be converted to binary or hexadecimal numbers through a process of division.

  • Decimal values such as kilo, mega, and giga are based on multiples of 1,000.

  • Binary values such as kibi, mebi, and gibi are based on multiples of 1,024.

  • Parallel transfers use eight wires or multiples of eight wires for data.

  • Serial transfers use a single wire (or pair or wires) for data.

  • Parallel transfers are faster than serial transfers performed at the same speed.

  • Fast serial interfaces such as USB, IEEE-1394, and Serial ATA are as fast or faster than parallel interfaces and will eventually replace most parallel-based interfaces.

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