computer world

 Logical Database model The logical database models are used in describing data at the conceptual and view level.However in contrast to conceptual database models, these model are to specify the overall logical structure of the database .These model are also known as record based logical database models. In the record based logical database models, the database is structured in fixed format re-cred of different types.Each record type define a fixed numbers of fields, or attributes an each field is of a fixed length. Relational database management system Relational database management system(RDBMS) is a software package used to store and retrieve data that is organised in the form of tables. Relational database management system, where all data are kept in tables or relations. Relational database management system are much more flexible and easy to use, in the comparison to other models. A Relational database management system(RDBMS) has following properties :   It store data in the fo

  Register and type of register in computer Architecture Register : register is very fast computer memory used to store data in execution. A register is consist of a group of flip-flop and gates. The flip flop hold the binary information and gates control when and how new information is transferred into a register. Types of register  Input/output adders register Input/output buffer register Program counter(PC) Data register Accumulator register(AC) Input/output address register : Each input/output device connector to our computer is mapped to a unique input/output address. These address are assigned to every input/output port on our computer. Including USB, Ethernet as well as any other ports or computer might having a unique address assign to each port allow our computer to easily recognize and locate device attache to computer.  Input/output buffer register : This register is used for exchanging the data between the input/output module and the processor.  Program counter (PC) : T

Definition of computer cables and types of cables Definition  of computer cables : A cable is one or more wires which are covered in plastic that transmitter power or data between devices and computers. A cables is also known as cord, connector or plug. Data cables provides communication between devices for example DVD and HDMI, USB cables and Cat 5. A power cable is used for supply the power and electricity. Types of cables : There are many types of cables used in computer science some of them are given below : Coaxial cable Twisted cable Optical cable Coaxial cable :   It is consist of a central copper wire surrounded  by a copper mess.  Coaxial cables are used for transmitting data at high rate. Coaxial tables are used by telephone companies to transmit data because cables handle  up to 40000 telephone calls simultaneously. Coaxial  cables group of specially wrapped and insulated wires.   Twisted pair cable : A twisted pair cable consist of two bunch of thin copper wires, each

  Definition of computer  ports and types of ports W hat is the definition of  Ports :   A port is a physical docking point using which an external device can be connected to the computer. It is important because information flows from a program to the computer or over the intern ate.  A port is a interface between the computer and other computers or peripheral devices. Two types of computer are used in the computers which are known as internal port and external port.  Internal ports are connects to the internal devices such as  hard drives, DVD drives. External port are connect to the external devices such as modem, printers and many other external devices. Characteristics of ports : A port has the following characteristics  External devices are connected to a computer using cables and ports. Ports are interface between external device as well as a computer. Types of computer ports : PS/2 port VGA port Modem port Ethernet port HDMI port PS/2 port : PS/2 port is stands for personal

 What is sound card, video card, TV tuner card and network adapter card Sound card :  Sound card is also known as audio card, sound sound board or audio output device. Sound card is a expansion card that provide the input and output of audio signals to and from a computer under control of computer programs. It is an expansion card for producing sound on computer that can be heard by speakers and headphones.  Uses of sound card :  Sound card is used for for providing the audio component  for multimedia application such as video auditing , audio auditing .It is also used in the field of education.  Video card :  It is an expansion card that connect to a computer motherboard. Video card is also known as video adapter or video controller. It is used to create a picture on display. TV tuner card : A  TV tuner card is like a television tuner that allow single to be received by a computer. TV tuner card have a function which is known as video capture card that is used for record the televisio

 Network adapter card Network adapter card  is also known as network adapter, Network interface card(NIC), LAN adapter . It is a hardware component design to allow computer to communication over a computer network.In other words we can say that a network interface card is a hardware component without which a computer can not connect with network. NIC means Network adapter card allow both wired and wireless communication and it also allow communication between many computers. Types of NIC : NIC cards are of two types 1. Internal network card : It requires network cables to provide network access. 2. External network card : In desktop computers and laptop that do not have internal NIC , external NIC were used. 

What is the slots/cards An expansion slots/card is computing circuit board that can be inserted into an expansion slot o f a computer motherboard to add additional functionality to a computer system the primary objective of an expansion card is to facilitated or expand fractures that not offered by the motherboard in simple way we can say that it provides an instillation point for a hardware. Expansion card to be connect there are many cards are available, some of them are given below : 1. Network adapter cards 2. SCSI cards 3. Sound cards 4. PC cards 5. Video cards   

  System bus System buses in computer are use to connect the measure component of a computer system.Information caries by data bus and address bus determine where it should be sent and a control bus to control it's operation. Simply we can say that buses are used in computer to connect it's components and transfer data between them. Buses may be serial or parallel . Parallel buses transfer data across multiple wires and serial buses transmitted data in single wires. System bus is a cable which capable of carrying signals from one place to another place a computer bus can be divided into two different types : Internal and External .  Internal bus connect the different component inside  the cabin-ate for example CPU and all other components on the motherboard.  The external bus connect the different external devices peripherals, extension slots, input output codes etc. Types of bus :  1. Address bus : A collection of wires used to identify particular information in main memory

 Motherboard :  Motherboard is a single platform to connect all the part of computer tougher . It connects the memory, CPU, sound card,hard disk, video card and other parts. Motherboard is also known as backbone of computer in other words we can say that motherboard is  the central printed circuit board in some complex electronic system such a personal computer motherboard is also known as main board, main circuit board, system board etc. Motherboard can be found in many devices it is the central circuit board of a computer. It provide a single socket for CPU where memory socket are available. Motherboard provide ports to attach a floppy drive to hard drive. Motherboard carries fans and a spacial parts design for power supply on the left side motherboard carry a number of ports to connect the monitor, printer, mouse, keyboard, speaker and network cable. Motherboard also provide USB ports which allow devices to be connected in plug and play manner. The first motherboard is considere

  Memory : A memory just like a human brain.It is used to store data and instructions. Computer memory is the storage space in the computer, where data is to be processed and instruction  required processing are stored. Computer memory is classified into following types : 1. Cache memory : Cache memory is a very high speed semiconductor memory which can speed up the CPU. It act as buffer(small storage are ) Between the CPU and main memory. We can say that it is a high speed memory between CPU and RAM and it is used temporary store very active data and instruction during processing.  2. Primary memory : Primary holds only that data and instruction on which the computer is currently working. Data holds by primary memory is lost when power is switched of. Primary is not fast as resisters. Primary is divided into two subcategory's : 1. RAM(Random access memory) : Random access memory is a form of computer memory that can be read and change in any any order typically used to store w

Input devices :   Input devices to be useful, a computer system needs to communicate with its external environment(its users).They are also known as peripheral devices.Input device are used to enter data from outside world  into primary storage.An inputs devices is an electronically device that accept  data from outside world and translate them into a form of a computer .   Following are some of the important input devices which are used in computer : 1. Keyboard   :  Keyboard devices are the most commonly used input device today they allow data and entry  into a computer system by pressing a set of keys. the most popular keyboard used today is the QWERTY keyboard. 2. Mouse :  Mouse is the most pointing device it is necessary input device in modern computer because they support GUI(graphical user interface) as their primary user interface.  3. Trackball :  Trackball is pointing device similar to a mouse it is a input device as the roller ball placed on the top with buttons.  4. Joys

Computer Generations                 G eneration in computer terminology is a change in technology. A computer is being use it provides a frame work of the growth of computer industry. The term "generation" was used to difference between hardware and software that together makeup a computer system. There are totally fife computer generation known till today. Although there is a certain amount of overlap between different generations, the approximate period show against each are normally accepted.                 The period first generation(1942-1955             The computer of first  generation used vacuum tubes as the basic component of memory of CPU. These tubes, like  electronic bulb, produced a lot of heat and the isolation used to fuse frequently therefore, they were very expensive and only large organization were able to it. Punch cards, paper-tape and magnetic-tape was used as input and output device. the computer of this generation used machine code as the programming

  What is computer and its characteristics  Computer  :  Computer is an electronic data processing device, which accept and store data input, process the data and generates the output in a required format. computer is made up of integrated  parts (input, control, ALU, storage and output unit) All the part work together to process data so, we can say that a computer is a programmable electronic device accept row data as input and process it with  set of instruction to produce the result as output. Meaning of computer The word "computer" comes from the word "compute" which means to "calculate". The word computer is derived from the Latin word compute which means to calculate. Characteristics of computer Automatic : It is a automatic machine work by itself without human instruction. Speed :  A computer is a very fast devices. It can perform in a few second, the amount of work that a human being can do in an entire year.  Accuracy : In addition to being very f

what is computer and what is the meaning of computer  What is computer  Computer is an electronic data processing device, which accept and store data input, process the data and generate the output in a required format .The word "computer" is comes from the word "compute" which means to "calculate". computer is made up of integrated parts  ( input unit, output output,control, ALU,storage).  A ll the part work together to process data so,we can say that a computer is a programmable electronic device accept row data as input and process it whit a set of instruction to produce it with a set of instruction to produce the result as output. The term computer is derived from  the Latin  word compute which means to calculate.      C haracteristics of computer   Automatic automatic means computer is a machine works by itself without human instruction. Speed  A computer is a very fast devices. No feelings computer are devoid of feeling because it is machine. No IQ