Presents the most up-to-date information in the rapidly changing world of computers and their software. Preparation for the CompTIA A+ Certification Exams is emphasized throughout the textbook. This textbook meets the requirements of the CompTIA Authorized Quality Curriculum Program, covering all objectives of the A+ Certification Exams. Most chapters open with descriptions of A+ Key Points, which identify chapter content that is likely to be represented on the examination. A+ Notes are used wherever appropriate in the text to highlight specific areas for exam preparation. At the end of most chapters, students take a 10-question quiz consisting of sample A+ exam items relating to the chapter content. A complete chapter of the textbook is devoted to CompTIA A+ exam preparation.