INFORMATION SYSTEM PARTS AND COMPUTER TYPES

INFORMATION SYSTEM PARTS AND COMPUTER TYPES

PARTS OF INFORMATION SYSTEM People are end users who use computers to make themselves more productive. Hardware refers to the physical components of your computer such as the system unit, mouse, keyboard, monitor etc. Software the collection of programs that provide step-by-step instructions for computer hardware. In another words software is the instructions that makes the computer work. There are two main types of software: System software and Application software. 1-2

PARTS OF INFORMATION SYSTEM Procedures are rules and guidelines to follow when using software, hardware, and data. They are documented in manuals by computer professionals. Data consists unprocessed facts including text, images, sounds.., programs process data into information which can be stored electronically as files. Connectivity is the capability of your computer to share information with other computers using wired or wireless connections.

TYPES OF COMPUTERS Supercomputers Mainframe computers Minicomputers (also known as mid-range computers) Microcomputers (also known as personal computers) 1-4

TYPES OF COMPUTERS Supercomputers: The most powerful type of computer Special high capacity used by large organizations. Ex. IBM s Blue Gene. Mainframe Computers: Not as powerful as supercomputer but they are capable of great processing speed and data storage. Minicomputers (midrange computers): Used by medium sized companies using them for specific purposes.

TYPES OF COMPUTERS Microcomputers: Are the least powerful, yet the most widely used type. There are six types: desktop media center (dedicated entertainment device) notebook (Laptop) netbook tablet PC handheld (PDAs, Smartphones)

TERMINALS Intelligent terminal: Performs a lot of the processing locally You could use a PC, linked to a mainframe Dumb terminal: Has very limited processing capabilities itself, but allows you to connect to a large powerful computer such as a mainframe. When you process your data from the dumb terminal, it is the mainframe at the other end of the network that is performing all the calculations.

FILES Data and programs are stored on your disk as files. There are different types of files, such as the files that you store your data in, the files that contain your programs and also files used to store your operating system. File name consists of two partitions: filename.extension (myletter.txt).

FILES From the extension you can predict the data type stored in the file and the program that can access this data. Some files extensions: txt, doc for text and some advanced text format. bmp, jpg form images. mp3, rm for audios. mp4, wav for vedios.

MEASUREMENTS OF COMPUTER MEMORY Bit All computers work on a binary numbering system, i.e. they process data in one's or zero's. This 1 or 0 level of storage is called a bit. Byte A byte consists of eight bits. Kilobyte A kilobyte (KB) consists of 1024 bytes. Megabyte A megabyte (MB) consists of 1024 kilobytes. Gigabyte A gigabyte (GB) consists of 1024 megabytes. Terabyte A terabyte (TB) consists of 1024 gigabytes.

HARDWARE

SYSTEM BOARD (MOTHERBOARD) Controls communications for the entire computer system. It is a circuit board covered with different electronic components including: Sockets: provide a connection point for small specialized electronic parts called chips. Chips: consist of tiny circuit boards. Slots: provide a connection point for specialized cards or circuit boards. These cards provide expansion capability for a computer. Bus lines: provide pathways that support communication among the various electronic components that either located on the system board or attached to the system board.

MOTHERBOARD Motherboard also contains: Central Processing Unit. Different memory types as RAM, ROM, Cache and internal HD.

CENTRAL PROCESSING UNIT (CPU) Electronic chip that performs most of the calculations within the computer and is responsible for the smooth running of your operating system as well as your application programs. So it is considered as the brain of the computer system. It determines how fast your computer will run and is measured by its GHz speed (some of the latest microcomputers has a CPU speed of 2GHz).

CPU Has two basic components: Control Unit (CU): tells the rest of the computer system how to carry out a program s instructions. Arithmetic logic Unit (ALU): Performs the arithmetic and logical operations. You can find special processors in smart cards, just like the one used in many universities, some cars to do some operations.

EXPANSION SLOTS AND CARDS

EXPANSION SLOTS AND CARDS Expansion Slots: Allow for new devices to be added Expansion cards are also called: Plug-in boards Controller cards Adapter cards Interface cards

EXPANSION SLOTS AND CARDS Examples of Expansion Cards: Graphics cards Sound cards Modem cards Network interface cards (NIC) PC cards and Express cards TV tuner cards

RADOM ACCESS MEMORY (RAM) Special type of memory chip attached on the motherboard, that hold programs and data that the CPU is presently processing so that it is called main storage. Is where the operating system is loaded and also where your applications are copied to when you load an application, such as a word processor or database program. So it is considered as the main 'working' memory used by the computer. RAM is called temporary or volatile storage because everything in RAM is lost as soon as the computer is turned off or the power is lost unlike secondary storage which you will learn about later so that it is a good practice to save your data every meanwhile.

RADOM ACCESS MEMORY (RAM) Its capacity is calculated in MB and GB As a rough rule, a Microsoft Windows based computer will operate faster if you install more RAM. For example for office 2007 to work effectively you need a minimum of 256MB of RAM to hold the program and another 512MB- 1GB for the OS.

CACHE MEMORY It improves processing by acting as a temporary high-speed holding area between the memory and the CPU. The CPU detects which information in RAM is frequently used and then copies that information into the cache, when needed the CPU can quickly access the information from the cache. Recently you can find PCs with 1GB cache memory.

READ-ONLY MEMORY (ROM) Are memory chips that have information stored by the manufacturer and are not volatile and cannot be changed by the user. CPU can read, or retrieve data and programs but the computer cannot write. Contain special instructions Needed to start a computer as in the ROM- BIOS. Put characters on screen. Handle basic keyboard input. Help in the functions of the video and network cards.

PERIPHERALS A peripheral device is any device that you can attach to your computer. Thus you could attach a scanner or modem to the back of your system unit.

INPUT/OUTPUT DEVICES

INPUT DEVICES Input devices convert what we understand into what the system unit can process.

KEYBOARDS Keyboards Traditional keyboards Ergonomic keyboards Wireless keyboards PDA keyboards Virtual keyboards Features Typewriter keyboard with numeric keypad

POINTING DEVICES Mouse: Mechanical Optical Cordless or wireless Three similar devices to mice Trackball Touch pads Pointing stick

POINTING DEVICES Joystick Touch Screen Stylus

SCANNING DEVICES Optical scanners Flatbed scanners Document scanners Portable scanners Card Readers Magnetic card readers Radio Frequency card readers

IMAGE CAPTURING DEVICES Digital cameras Images recorded digitally on a disk Images can be downloaded to a computer Digital video cameras Records motion digitally Can take still images as well WebCams Specialized digital video cameras Broadcast images over the Internet

AUDIO-INPUT DEVICES Voice recognition systems Use a microphone, a sound card, and special software Users can operate computers and create documents using voice commands

OUTPUT DEVICES Output devices convert what the system unit has processed into a form that we can understand.

MONITORS Known as screens or display screens Output referred to as soft copy Features Resolution/pixels Refresh rate Size

MONITORS Cathode-ray tube (CRT) monitors Flat-panel monitors Require less power to operate Portable and thinner than CRTs Other monitors E-books readers Data projectors High-definition television (HDTV)

PRINTERS Output referred to as hard copy Features Resolution Color capability Speed Ink-jet printer Laser printer Personal laser printers Shared laser printers Thermal printer Other printers Dot-matrix printers Plotters Photo printers Portable printers

AUDIO-OUTPUT DEVICES Translates audio information from the computer into sounds that people can understand Common devices Speakers Headphones Digital Music Players ipod iriver

SECONDARY STORAGE

SECONDARY STORAGE Data storage has expanded from text and numeric files to include digital music files, photographic files, video files, and much more. These new types of files require secondary storage devices with much greater capacity than floppy disks. Provides permanent or nonvolatile storage. Data and programs can be retained after the computer has been shut off. Most desktop microcomputer systems have hard and optical disk drives

HARD DISKS (HD) Use thicker, metallic platters for storage Faster than a floppy diskette Large capacity Sensitive Instruments Speed is known as the average access time and is measured in milliseconds.

HARD DISK Internal Hard Disk: Located inside system unit Designated as the C drive Advantages over other removable media Capacity 60GB to TB. Access speed which is faster than other storage devices.

EXTERNAL HARD DISK External Hard Disk: Removable hard disks Used to complement internal hard disk Capacities of 20 to 500 GB

SOLID-STATE STORAGE Flash memory cards Widely used in notebook computers Used to record MP3 music files USB Drives Flash drives Very compact Capacity from 1 GB to 256 GB

OPTICAL DISKS Compact Disc (CD): Optical format From 650 MB to 1 GB capacity Rotation speeds vary Three basic types Read only: CD-ROM Write once: CD-R Rewriteable: CD-RW Digital Versatile Disc (DVD): Digital Versatile Disc or Digital Video Disc (DVD) Similar to CDs, but can store more data from 4.7 to 17GB Three basic types Read only: DVD-ROM Write once: DVD+R; DVD-R Rewritable: DVD+RW; DVD-RW; DVD-RAM

COMPUTER PERFORMANCE CPU speed RAM size Hard disk speed and capacity

SOFTWARE

SOFTWARE TYPES Software is another name of programs, it is instructions that tells the computer what to do and process the data into the information you want. There are two types of Software: System Software Application Software

SYSTEM SOFTWARE Is a background software that helps the computer manage its own internal resources. People interact with application software, System software enables applications to interact with computer hardware. System software is a collection of programs including the following: Operating Systems. Utilities (Specialized programs to make computing easier). Device drivers (Specialized programs that allow communication between a device and the computer).

OPERATING SYSTEMS A collection of programs that handle technical tasks The operating system allows you to use the advanced features of a modern computer without having to learn all the details of how the hardware works Manage computer resources Provide an interface between the users and computer Runs applications Every computer has an operating system Stored in memory and loaded into RAM once the computer is turned on

FUNCTIONS OF OS Performs three types of functions Manages computer resources Coordinate memory, processing storage, and printers Monitor system performance Provide security Start-up the computer Provides user interface Character-based interface (Using written commands ex. DOS) Graphical user interface (GUI)

FUNCTIONS OF OS Runs applications Loads and runs applications such as word processor. Most OSs supports Multitasking( The ability to switch between different applications stored in memory such as hearing songs and printing homework).

GRAPHICAL USER INTERFACE (GUI) A Graphical User Interface (GUI) is simply an additional part of the modern operating systems that displays windows and drop down menus, and also enables you to drive your computer using a mouse. Examples of operating system that use a GUI include Windows Operating Systems, MAC, Linux..

ADVANTAGES OF GUI All programs look similar. When you switch from a program supplied by one manufacturer to one from a different manufacturer, you will find the transition very easy. Application programs work in the same way as the underlying operating system. The GUI also allows programmers to easily write consistent looking programs.

FEATURES OF OSS Booting: Starting or restarting the computer. Worm booting means restarting the computer without turning it off, cold booting means restarting the computer after turning off. Have several features with application software: Icons: graphic representation as a program. Pointer: controlled by a mouse. Windows: rectangular areas for displaying information and running programs. Menus: provide a list of options or commands. Dialog Boxes: provide information or request input. Help: provide online assistance for OS procedures and functions.

CATEGORIES OF OSS Embedded Os: Used with handheld computers and stored within the device. Networking OS (NOS): controls and coordinates networked computers and located on the servers. Stand-alone OS: Also known as desktop OS, controls a single computer, located on the hard disk

EXAMPLES OF OSS Windows: One of the most popular OS and can run many type of applications, produced by Microsoft, comes in many versions(3.1, 95, 98, NT, 2000, XP, Vista, 7). Mac OS: produced by apple, it is a powerful easy to use OS popular with professional graphic designers. Unix and Linux: Unix originally designed to run on minicomputers in network environments, now it is also used by powerful microcomputers and by servers on the web. There are many versions one recently is Linux which is a popular powerful alternative to windows.

APPLICATION SOFTWARE Can be described as end user software that can be used to accomplish a variety of tasks. Can be categorized as basic and specialized software. Basic applications: programs that are widely used in every discipline and occupation such as word processor, database management system, spreadsheets presentation programs, and internet browsers. Specialized applications: programs that are more focused on specific disciplines and occupations.

BASIC APPLICATIONS Word Processor: create text-based documents and are one of the most flexible and widely used software. Used to create letters, memos, faxes, books.. MSWord, Corel WordPerfect and Apple Pages are examples of word processors. Spreadsheets: Organize, analyze and graph numeric data such as budgets and financial reports. MSExcel, Apple iwork s Numbers, and Corel Quattro Pro.

BASIC APPLICATIONS Database Management Systems (DBMS): A database is a set of related data. A DBMS is a program that sets up or structures a database. It also provides tools to edit, enter, retrieve data from a database. Collages keeps information about their students, teachers, courses in a database. Related information about students are stored in records, a student record could have his name, address, major, birthdate.. MSAccess, Corel Paradox, Lotus Approach. Presentation Graphics: Programs that combine a variety of

SPECIALIZED APPLICATIONS Specialized applications make it possible to perform advanced tasks at home. Home users can create Webs sites, work with graphic images, and create music or art. Graphics programs Audio and video editing software Multimedia Web authoring Artificial intelligence

MULTIMEDIA The integration of a variety of media into one presentation Video Music Voice Graphics Text

SYSTEM DEVELOPMENT PHASES Feasibility Study. System Analysis. Design. Development. Implementation. Maintenance.