COMPUTER LITERACY Hardware and Software To be computer literate, you must be familiar enough with computers that you understand their capabilities and limitations and know how to use them.
INTRODUCTION • Information technology (IT) - any computer-based tool that people use to work with information and support the information and information-processing needs of an organization • Hardware - consists of the physical devices associated with a computer system • Software - the set of instructions that the hardware executes to carry out specific tasks
Hardware Basics • Computer -an electronic device operating under the control of instructions stored in its own memory that can accept, manipulate, and store data • Hardware components: • Central processing unit (CPU) • Primary storage • Secondary storage • Input device • Output device • Communication device
Central Processing Unit • Central processing unit (CPU) (or microprocessor) - the actual hardware that interprets and executes the program (software) instructions and coordinates how all the other hardware devices work together • The CPU contains 2 main parts: • Control unit -interprets software instructions and literally tells the other hardware devices what to do, based on the software instructions • Arithmetic-logic unit (ALU) -performs all arithmetic operations (for example, addition and subtraction) and all logic operations (such as sorting and comparing numbers)
Central Processing Unit • The number of CPU cycles per second determines the speed of a CPU • Hertz (Hz) • Megahertz (MHz) - the number of millions of CPU cycles per second • Gigahertz (GHz) - the number of billions of CPU cycles per second
Central Processing Unit • Computers are digital, meaning that the data they process, whether it be text, sound, graphics, or video, is first converted into a digital (numeric) value. • Only the digits 0 and 1 are used. • Only two digits are used because they can be easily represented electronically by circuits in the computer being either off or on. • This numbering system is referred to as the binary language. 0 = Off 1 = On • Bit: Each off or on digital value—the smallest unit of data handled by a computer. Bit is short for BInarydigiT. • Byte: A group of 8 bits—can be thought of as a character (letter, number, symbol, mark of punctuation, space, etc.).
RANDOM ACCESS MEMORY (RAM) • Random access memory (RAM) - the computer’s primary working memory, in which program instructions and data are stored so that they can be accessed directly by the CPU via the processor’s high-speed external data bus • Volatile (temporary) • Primary Storage
READ ONLY MEMORY (ROM) • ROM (read only memory): contains permanent programs or data recorded in the memory by the manufacturer. • ROM is used to store the instruction set of a computer—BIOS, basic input/output system. • It retains its contents when the power of the computer is turned off. It is nonvolatile. • Data or programs in ROM can be read but not changed. • Many special-purpose computers used in automobiles, appliances, etc. use a small amount of ROM.
STORAGE DEVICES • Storage Devices - consists of equipment designed to store large volumes of data for long-term storage • Referred to as secondary storage • Permanent or non-volatile
Secondary Storage
Secondary Storage • Hard drives • Optical drives • CD Drive • DVD Drive • Combo CD/DVD Drive • Blu-Ray Drive (BD) • Memory cards • SD • Compact flash • Memory sticks • USB drives • Pen drives • Flash drives • Jump drives • Thumb drives
INPUT DEVICES • Input device - equipment used to capture information and commands • Keyboard • Mouse • Microphone • Touch Screen • Digital Camera • Bar Code Scanner • Biometric Input Devices
OUTPUT DEVICE • Output device -equipment used to see, hear, or otherwise accept the results of information processing requests • Monitors • Cathode-ray tube (CRT) • Liquid crystal display (LCD) • Printers • Laser printer • Ink-jet printer • Plotter • Speakers
Communication Device • Communication device -equipment (modem) used to send information and receive it from one location to another • Dial-up access • Broadband access • Cable • Fiber-optic Service (FiOS) • Digital subscriber line (DSL) • Satellite • Wireless
COMPUTER CATEGORIES • PC • Mobile Devices • Personal digital assistant (PDA) • Laptop • Tablet • Workstation • Minicomputer • Mainframes • Supercomputers
2 CATEGORIES OF SOFTWARE There are two categories of software— • System software -controls how the various pieces of hardware work together along with the application software • Operating system software • Utility software • Application software - consists of programs that tell a computer how to produce information
UTILITIES • Types of utility software • Installation Wizards and Uninstall wizards • File compression utilities • Disk cleanup • Disk defragmenter • Scan disk (Error checker) • System Restore • Backup • AntiSpyware • AntiVirus
Application Software • Types of application software • Bowser • Database management • Desktop publishing • Email • Games/Entertainment • Presentation graphics • Spreadsheet • Word processing • Accounting software
HOME WORK • READING: • Business Plugin B3, Hardware & Software • Online: www.LagProfi.com • Do: • Computer Literacy Review Sheet • Online: www.LagProfi.com
LEARNING OUTCOMES • Describe the six major categories of hardware and provide an example of each • Identify the different computer categories and explain their potential business uses • Explain the difference between primary and secondary storage
LEARNING OUTCOMES • List the common input, output, storage, and communication devices • Describe the eight categories of computers by size • Define the relationship between operating system software and utility software
