How Will I Use an Operating System?

The user interface of an operating system is the portion of the program with which users interact.The user interface can be1. Command-line,2.Menu-driven, and3.Graphics-based.A command-line interface requires a user to type the desired response at a prompt using a special command language.To be an effective user of any command-line software, you must memorize its commands and their exact syntax-no easy task.A menu-driven interface allows the user to select commands from a list (menu) using the keyboard or a pointing device such as a mouse.A graphical user interface (GUI):The trend is away from text-based, command-line interfaces to user-friendly, graphics-oriented environment called a graphical user interface (GUI).Graphical user interfaces rely on graphics-based software.Graphic-based software...

Type of Processing

A multiprocessing operating system allows the simultaneous execution of programs by a computer that has two or more CPUs. Each CPU can be either dedicated to one program, or dedicated to specific functions and then used by all programs.Interprocessing, also called dynamic linking, is a type of processing that allows any change made in one application to be automatically reflected in any related, linked application.Real-time processing allows a computer to control or monitor the performance of other machines and people by responding to input data in a specified amount of time.Virtual-machine (VM) processing creates the illusion that there is more than one physical machine. VM capabilities permit a computer to run numerous operating systems at one time. VM capabilities are typically used on...

Major Functions of Operating Systems

The major functions of an OS are:-resource management,-data management,-job (task) management, and-standard means of communication between user and computer.The resource management function of an OS allocates computer resources such as CPU time, main memory, secondary storage, and input and output devices for use.The data management functions of an OS govern the input and output of the data and their location, storage, and retrieval.The job management function of an OS prepares, schedules, controls, and monitors jobs submitted for execution to ensure the most efficient processing. A job is a collection of one or more related programs and their data.A job is a collection of one or more related programs and their data.The OS establishes a standard means of communication between users and their...

Operating System

What Is an Operating System?An operating system (OS) is a core set of programs that control and supervise the hardware resources of a computer and provide services to other system software, application software, programmers, and users of a computer.The OS gives the computer the instructions it needs to operate, telling it how to interact with hardware, other software, and the user.The OS establishes a standard interface, or means of communication, between users and their computer systems.When you power up a computer, you boot the system.The booting procedure is so named because the computer "pulls itself up by its own bootstraps" (without the assistance of humans).When booting the system,First, a program in read-only memory (ROM) initializes the system and runs a system check to verify that...

Computer language-oriented software includes

language translators such as assemblers, interpreters, and compilers.Program generators (programs that automatically generate program code), debugging and testing programs.Utilities are programs that are purchased as separate products; they perform a wide range of functions. This type of software includes products such as -data conversion programs that convert data from one format to another,-data recovery programs that restore damaged or accidentally erased data,-librarians that log and track the locations of disk or tape program files, -security and auditing programs, and -merge and sort programs.Application software refers to programs that...

Categories of Software

Knowledge the Rooms in the HouseComputer hardware cannot perform alone.Software refers to the instructions that direct the operations of a computer.There are two basic types of software:-system software (controls hardware), and-application software (performs specific tasks).System software refers to programs designed to perform tasks associated with directly controlling and utilizing computer hardware.-It does not accomplish specific tasks for a user, such as creating documents or analyzing data.-System software includes:-Operating systems (the most important type of system software),-Data management software,-Computer language-oriented software, and-Utilities that help users perform various functions.-Data management software includes:-database and file management programs that manage data...

Interactive With The System

To interact effectively with a computer, user needs to be knowledgeable in four areas.1.General software concepts (for example, windows, menus, uploading, and so on)2.The operation and use of the hardware over which you have control (such as the PC, magnetic disk, and printer).3.The function and use of the computer's operating system and/or its graphical user interface (GUI), both of which provide a link between the user, the computer system, and the various applications.4.The specific applications programs you are usingThe first three areas are prerequisites to the fourth because you will need a:working knowledge of software concepts,hardware, andthe operating system and/or a GUIbefore you can make effective use ofQuicken (accounting),Harvard Graphics (presentation graphics),Paradox...

COMMUNICATION AND NETWORK CONCEPTS

Evolution of Networking: ARPANET, Internet, Interspace.Different ways of sending data across the network with reference to switchingtechniques.Data Communication terminologies: Concept of Channel, Baud, Bandwidth (Hz, KHz, MHz) and Data transfer rate (bps, kbps, Mbps, Gbps, Tbps).Transmission media: Twisted pair cable, coaxial cable, optical fiber, infrared, radio link, microwave link and satellite link.Network devices: Modem, RJ45 connector, Ethernet Card, Hub, Switch, Gateway.Different Topologies- Bus, Star, Tree; Concepts of LAN, WAN, MAN.Protocol: TCP/IP, File Transfer Protocol (FTP), PPP, Level-Remote Login (Telnet), Internet, Wireless/Mobile Communication, GSM, CDMA, WLL, 3G, SMS, Voice mail, Application Electronic Mail, Chat, Video Conferencing.Network Security Concepts: Cyber Law,...

COMPUTER SYSTEM ORGANISATION

Number System: Binary, Octal, Decimal, Hexadecimal and conversion between two different number systems. Integer, Floating Point, 2�s complement of number from base-2;Internal Storage encoding of Characters: ASCII, ISCII (Indian scripts Standard Code for Information Interchange), UNICODE;Microprocessor: Basic concepts, Clock speed (MHz, GHz), 16 bit, 32 bit, 64 bit processors; Types � CISC, RISC; Concept of System Buses, Address bus, Data bus.Concepts of Accumulator, Instruction Register, and Program Counter;Commonly used CPUs and CPU related terminologies: Intel Pentium Series, Intel Celeron, Cyrix, AMD Series, Xeon, Intel Mobile, Mac Series; CPU Cache;Concept of heat sink and CPU fan, Motherboard; Single, Dual and Multipleprocessors;Types of Memory: Cache (L1,L2), Buffer, RAM (DRAM, SDRAM,...

Network �Architectures�

A host refers to any device that is connected to your network. Some define ahost as any device that has been assigned a network address.A host can serve one or more functions:� A host can request data (often referred to as a client)� A host can provide data (often referred to as a server)� A host can both request and provide data (often referred to as a peer)Because of these varying functions, multiple network �architectures� have been developed, including:� Peer-to-Peer networks� Client/Server networks� Mainframe/Terminal networksWhen using a peer-to-peer architecture, all hosts on the network can bothrequest and provide data and services. For example, configuring two Windows XP workstations to share files would be considered a peer-to-peer network.Though peer-to-peer networks are simple...

- Introduction to Networks -

What is a Network?A network is defined as devices connected together to share information and services. The types of data/services that can be shared on a network is endless - documents, music, email, websites, databases, printers, faxes, telephony, videoconferencing, etc.Protocols are �rules� that govern the method by which devices share data and services. Protocols are covered in great detail in subsequent sections.Basic Network TypesNetworks are generally broken down into two types:LANs (Local Area Networks) - a high-speed network that covers a relatively small geographic area, usually contained within a single building or campus. A LAN is usually under the administrative control of a single entity/organization.WANs (Wide Area Networks) � The book definition of a WAN is a network that spans...

Number Systems and Binary Arithmetic

Number SystemsThis focuses on the way communication takes place inside and among different computer devices.Types of number systems:1. Decimal (Denary): In primary school we used to write numbers in terms of Units, Tens, Hundreds and Thousands. Our number system, the DENARY system, bases itself on TEN states 0, 1, 2, 3, 4, 5, 6, 7, 8, 92. Binary: A numbering system using the digits "0" and "1" in the decimal system. We know that computers are machines built from microscopic switches with only TWO states: ON or OFF (0 or 1). All computer programs are executed in binary form only. When a user enters data into a computer (such as inputting letters) a translator has to convert that inputted data into its binary equivalent.3. Hexadecimal: This is a numbering system involving 16 states and is used...

Logic circuits

Electronic circuits which process information encoded as one of a limited set of voltage or current levels. Logic circuits are the basic building blocks used to realize consumer and industrial products that incorporate digital electronics. Such products include digital computers, video games, voice synthesizers, pocket calculators, and robot controls.All logic circuits may be described in terms of three fundamental elements, shown graphically in the illustration. The NOT element has one input and one output; as the name suggests, the output generated is the opposite of the input in binary. In other words, a 0 input value causes a 1 to appear...

Number systems and computer codes

Computer works with binary number system that is consist of only two digits zero and one. Inside the computer binary number is represented by an electrical pulse. One means a pulse of electricity and zero means no pulse. All the data enters into the computers first converts into the binary number system. One digit in binary number system is called bit and combination of eight bits is called byte. A byte is the basic unit that is used to represent the alphabetic, numeric and alphanumeric data.Data is the combination of characters, numbers and symbols collected fro a specific purpose.Data is divided into three types; alphabetic data, numeric data...

Data Types

A data type is a type of data. Of course, that is rather circular definition, and also not very helpful. Therefore, a better definition of a data type is a data storage format that can contain a specific type or range of values.When computer programs store data in variables, each variable must be assigned a specific data type. Some common data types include integers, floating point numbers, characters,strings, and arrays. They may also be more specific types, such as dates, timestamps, boolean values, and varchar (variable character) formats.Some programming languages require the programmer to define the data type of a variabl before assigning it a value. Other languages can automatically assign a variable's data type when the initial data is entered into the variable. For example, if the...

Computer software

What is Software?Software is a set of instruction written to interface between user and machine.Who writes this instructions?Programmers writes this instructions.How the programmers write the instructions /software?They use computer languages to write software applications.Software can be divided into three main categories:- Languages- Applications- Operating Systems (OS)LANGUAGE:It is one of the software type, use to write extensive applications and operating systems It did not contains any limitations in programming. By using the languages you can write any thing for a computer.For instance just imagine a language like a piece of cloth with that you want to make a shirt or paint curtain for windows or door, than you will take that cloth to the tailor and have him made for you or if you know...

Types of Computers

Definition of a ComputerA computer can be defined as an electronic device that receives input from the user through a mouse or keyboard, processes it in some fashion and displays the result on a screen. It can also be assumed as any device that has a microprocessor in it.Types of ComputersFundamentally, there are two types of computersanalog digitalAnalog computers solve problems by using continuously changing data such astemperature pressure voltage Digital computers solves problems by manipulating discrete binary digits (1s and 0s).3 Main Types of Computersmainframes minicomputersmicrocomputersThey differ in size, speed of operation, amount of data that can be stored, and the number of simultaneous users.Microcomputers:Personal or desktop computer designed for general use by a single person.Home...