Plug-in B 3 HARDWARE & SOFTWARE Mc. Graw-Hill/Irwin © 2008 The Mc. Graw-Hill Companies, All Rights Reserved
5 -2 INTRODUCTION • Information technology (IT) – computer-based ______ – that people use – to support the information-processing needs of an _______ • Computer system consists of – Hardware - consists of the physical devices associated with a computer system – Software - the set of ______ that the hardware executes to carry out specific tasks
5 -3 HARDWARE BASICS • Computer – an electronic device operating under the control of instructions stored in its own ______ that can accept, manipulate, and store data • Hardware components include: 1. 2. 3. 4. 5. 6. Central processing unit (CPU) Primary storage ______ storage Input device Output device Communication device
5 -4 Central Processing Unit (CPU) • CPU (or _________) – Executes the program (software) instructions – Coordinates all the other hardware devices • Parts of the CPU – Control unit • interprets software instructions • literally tells the other hardware devices what to do – Arithmetic-logic unit (ALU) • Performs ______ operations • Performs logic operations (such as sorting and comparing numbers)
5 -5 Central Processing Unit • The number of CPU cycles per second determines the speed of a CPU – Megahertz (MHz) - the number of _____ of CPU cycles per second – Gigahertz (GHz) - the number of _____ of CPU cycles per second
5 -6 Central Processing Unit • CPU speed factors – – Clock speed—rate at which instructions are performed Word length—number of bits processed at each cycle _____ width—number of “lanes” for signals to travel Chip line width—distance between transistors in a chip • Binary digit (bit) – the smallest unit of information that a computer can process • Byte – a group of ______ bits representing one natural language character – 01000001 = A
5 -7 Primary Storage • Primary storage – the computer’s main memory – directly accessible to the _____ – consists of • random access memory (RAM)—high speed • ____ memory—very high speed • read-only memory (ROM)—fixed set of instructions
5 -8 Random Access Memory (RAM) • Random access memory (RAM) – the computer’s primary working memory • RAM stores – Program instructions – ______ • Characteristics of RAM – High-speed access – Volatility (when _______ goes off)
5 -9 Read-Only Memory (ROM) • Read-only memory (ROM) - the portion of a computer’s primary storage that does not lose its contents when one switches off the power – Flash memory – Memory card – Memory stick
5 -10 Secondary Storage • Secondary storage - consists of equipment designed to store large volumes of data for long-term storage – Megabyte (MB or Meg) - roughly 1 million bytes – Gigabyte (GB) - roughly 1 billion bytes – Terabyte (TB) - roughly 1 _______ bytes
5 -11 Magnetic Medium • Magnetic medium - a secondary storage medium that uses magnetic techniques to store and retrieve data on disks or tapes coated with magnetically sensitive materials – Magnetic tape - an older secondary storage medium that uses a strip of thin plastic coated with a magnetically sensitive recording medium – Hard drive - a secondary storage medium that uses several rigid disks coated with a magnetically sensitive material and housed together with the recording heads in a hermetically sealed mechanism
5 -12 Other Media • Optical medium: – Compact disk-read-only memory (CD-ROM) – Compact disk-read-write (CD-RW) drive – ____ video disk (DVD) – DVD-ROM drive – Digital video disk-read/write (DVD-RW) • Flash memory – Electrically _____ Programmable Read -Only Memory (EEPROM) – ‘flash drives’
5 -13 Input Devices • Input device - equipment used to capture information and commands – Manual input devices • Joystick • Keyboard • Microphone – Automated input devices • Bar code scanner • Digital camera • Magnetic ____ character reader
5 -14 Output Devices • Output device - equipment used to see, hear, or otherwise accept the results of information processing requests – Cathode-ray tube (CRT) – ____ crystal display (LCD) – Laser printer – Ink-jet printer – Plotter
5 -15 Communication Devices • Communication device - equipment used to send information and receive it from one location to another – Dial-up access – Cable – Digital subscriber line (DSL) – Wireless – Satellite
5 -16 COMPUTER CATEGORIES • Computer categories include: – Personal digital assistant (PDA) – Laptop – Tablet – _____ – Workstation – Minicomputer – Mainframe computer – Supercomputer
5 -17 SOFTWARE BASICS • System software - controls how the various technology tools work together along with the application software – _____ system software • Windows, Mac, Linux – Utility software • Backup • Recovery • Security – Application software
5 -18 Application Software • Most common types of application software – Browser: for surfing the Internet – Database management: accessing large amounts of data – E-mail: communication – Presentation graphics: slide shows – Spreadsheet: performing complex calculations – Word processing: creating documents
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