Chapter 2 – Part 1 Hardware and Software

Why Learn About Hardware and Software? Fundamentals of Information Systems, Sixth Edition 2  Organizations invest in computer hardware to:  Improve worker productivity  Increase revenue, reduce costs  Provide better customer service

What is Hardware ? Fundamentals of Information Systems, Sixth Edition 3  Hardware refers to the physical components of a computer that perform the input, processing, storage, and output activities of the computer.

Hardware Components (continued) Fundamentals of Information Systems, Sixth Edition 4  System unit:  Houses the components responsible for processing (the CPU and memory)  All other computer system devices:  Are linked either directly or indirectly into the system unit housing

Hardware Components (continued) Fundamentals of Information Systems, Sixth Edition 5 System unit

System Unit Components 6  Central Processing Unit (CPU): The part of the computer that consists of three associated elements:  Arithmetic/logic unit  the control unit  the register areas

CPU Components Fundamentals of Information Systems, Sixth Edition 7  Arithmetic/logic unit (ALU):  Performs mathematical calculations and makes logical comparisons.  Control unit:  Sequentially accesses program instructions, decodes them, and coordinates the flow of data in and out of the ALU, registers, primary storage, and even secondary storage and various output devices.  the register areas  A special, high-speed storage area. All data must be represented in a register before it can be processed.

Processing and Memory Devices: Power, Speed, and Capacity 8  Primary memory holds program instructions and data, is closely associated with the CPU.

Processing Characteristics and Functions 9 - organizations use a variety of measures to measure processing speed.  Clock speed:  Series of electronic pulses produced at a predetermined rate that affects machine cycle time  Often measured in: Megahertz (MHz): millions of cycles per second Gigahertz (GHz): billions of cycles per second  Physical characteristics of the CPU  Most CPUs are collections of digital circuits imprinted on silicon wafers, or chips.  Electrical current must flow through a medium from point A to point B.  The speed at which it travels between points can be increased by either reducing the distance between the points or reducing the resistance of the medium to the electrical current.

Memory Characteristics and Functions Fundamentals of Information Systems, Sixth Edition 10  Memory:  Located physically close to the CPU to decrease access time  Provides the CPU with a working storage area for programs and data  Rapidly provides data and instructions to the CPU  Storage capacity:  Data is stored in memory as a combination of on or off circuit states.  byte (B): Eight bits that together represent a single character of data.

Fundamentals of Information Systems, Sixth Edition 11 Memory Characteristics and Functions (continued)

Types of Memory Random Access Memory (RAM) Read-Only Memory (ROM) 1.Volatile memory 2.RAM chips consist of millions of switches that are sensitive to changes in electric current. 3.Read/write memory 1.Permanent storage 2.NonVolatile 3.programs and data from the computer manufacturer 4.Can be read, but not overwritten

Multiprocessing Fundamentals of Information Systems, Sixth Edition 13  Multiprocessing:  Simultaneous execution of two or more instructions at the same time.  There are a number of forms of multiprocessing: 1. Multicore microprocessor:  Combines two or more independent processors into a single computer to share the workload and boost processing capacity.

Multiprocessing (continued) Fundamentals of Information Systems, Sixth Edition Parallel computing:  Simultaneous execution of the same task on multiple processors to obtain results faster  The most frequent uses for parallel computing include modeling, simulation, and analyzing large amounts of data.

Secondary Storage Fundamentals of Information Systems, Sixth Edition 15

Secondary Storage Fundamentals of Information Systems, Sixth Edition 16  Secondary storage:  Compared with memory, offers the advantages of: Nonvolatility greater capacity greater economy.  Considerably slower than memory.

Secondary Storage Fundamentals of Information Systems, Sixth Edition 17  The selection of secondary storage media and devices requires understanding their primary characteristics:  Access method  Capacity  Portability.

Access Methods 18 Data and information access can be either sequential or direct.  Sequential access:  Data is stored and retrieved in a sequential process.  Must be accessed in sequence by searching through prior data.  Devices used called sequential access storage devices (SASDs) such as : Magnetic tape.  Direct access:  Records can be retrieved in any order  Devices used are called direct access storage devices (DASDs) such as magnetic disks.

Secondary Storage Devices 19  Magnetic tapes:  Primarily for storing backups of critical organizational data  magnetized to represent bits  sequential access storage medium  access is slower, and usually less expensive than disk storage.  Magnetic disks:  Direct -access storage device.  fast data retrieval  high capacity  Reasonable cost Hard Disk Drives & Floppy Disks (diskettes)

Secondary Storage Devices (continued) 20  Optical discs:  Common form of optical disc on which data cannot be modified once it has been recorded: compact disc read-only memory (CD-ROM) CD-recordable (CD-R) CD-rewritable (CD-RW)  Digital video disc (DVD):  Storage medium used to store software, video games, and movies  A Universal Serial Bus (USB )  USB flash drives are external to the computer and are removable and rewritable.

Input Devices Fundamentals of Information Systems, Sixth Edition 21

Input Devices 22  Devices used to input general types of data: 1. Personal computer input devices A keyboard and a computer mouse are the most common devices used for entry of data 2. Speech recognition technology Enables a computer equipped with a source of speech input such as a microphone to interpret human speech as an alternative means of providing data or instructions to the computer. Speech recognition SW requires voice recognition training. Discrete speech recognition: requires pauses between each word. Continuous speech recognition (CSR) recognizes continuous speech.

Input Devices Digital cameras record and store images or video in digital form 4. Touch-sensitive screens Display screens which function as input as well as output devices. By touching certain parts of a sensitive screen, you can execute a program or cause the computer to take an action 5. Optical data readers Special scanning device to scan documents. Optical mark recognition (OMR) readers for test scoring. Optical Character recognition (OCR) readers use reflected light to recognize and scan various characters. Can convert handwritten or typed documents into digital data

Input Devices (continued) Fundamentals of Information Systems, Sixth Edition 24  Radio Frequency Identification (RFID) A technology that employs a microchip with an antenna to broadcast its unique identifier and location to receivers.

Output Devices Fundamentals of Information Systems, Sixth Edition 25

Output Devices Fundamentals of Information Systems, Sixth Edition Display monitors Used to display the output from the computer  Types:  Cathode-Ray Tube (CRTs): Used to display images,it generate one or more electron beams. A dot on the screen called a pixel lights up.  Plasma display: Uses thousands of smart cells (pixels) consisting of electrodes and neon and xenon gases that are electrically turned into plasma to emit light  LCD displays: Flat displays that use liquid crystals Cathode-Ray Tube (CRTs)

Output Devices (continued) Fundamentals of Information Systems, Sixth Edition Printers and plotters:  Two main types of printers are laser printers and inkjet printers  Plotters are a type of hard-copy output device used for general design work

Output Devices (continued) Fundamentals of Information Systems, Sixth Edition Digital audio player  Can store, organize, and play digital music files 4- E-books:  Digital media equivalent of a conventional printed book

Computer System Types 29 Fundamentals of Information Systems, Sixth Edition

Computer System Types Fundamentals of Information Systems, Sixth Edition 30  Computer systems:  Can range from desktop (or smaller) portable computers to massive supercomputers that require housing in large rooms

Computer System Types 31 Computer System Types Portable Computers Nonportable Computers Nonportable Single-User Computers Multiple-User Computer Systems

1- Portable Computers Fundamentals of Information Systems, Sixth Edition 32  They are small enough to carry easily. Portable computers include :  handheld computers  laptop computers  notebook computers  netbook computers  tablet computers.

Portable Computers (continued) Fundamentals of Information Systems, Sixth Edition 33  Handheld computers:  Single-user computers that provide ease of portability because of their small size.  Laptop computer:  Personal computer designed for use by mobile users  Notebook computers:  Lightweight computer that weighs less than 5 pounds

Portable Computers (continued) 34  Netbook computer:  The smallest, lightest, least expensive member of the laptop computer family  Tablet computers:  Portable, lightweight computers with no keyboard  Smartphone:  Combines the functionality of a mobile phone, camera, Web browser, tool, MP3 player, and other devices

2- Nonportable Single-User Computers 35  Thin client:  Low-cost, centrally managed computer with no extra drives (such as CD or DVD drives).  Desktop computers:  A relatively small, inexpensive, single-user computer that is highly versatile. Thin client computer Desktop computer

Nonportable Single-User Computers (continued) 36  Workstations:  More powerful than personal computers but still small enough to fit on a desktop.  used for mathematical computing, computer-aided design, and other high-end processing.

2- Multiple-User Computer Systems Fundamentals of Information Systems, Sixth Edition 37  Server:  More powerful than workstations.  Used by many users to perform a specific task, such as running network or Internet applications

Multiple-User Computer Systems (continued) Fundamentals of Information Systems, Sixth Edition 38  Mainframe computer:  Large, powerful computer shared by hundreds of concurrent users connected to the machine over a network  Supercomputers:  The most powerful computers with the fastest processing speed and highest performance Mainframe computer Supercomputers

Computer System Types (continued) Fundamentals of Information Systems, Sixth Edition 39

Computer System Types (continued) Fundamentals of Information Systems, Sixth Edition 40