INRODUCTION

COMPUTING DEVICES

Computing is usually defined as the activity of using and developing computer technology, computer hardware and software.

Device that performs certain arithmetic and logical operations without any errors is known as computing devices.

Now computing devices are the one’s that perform some computational operations using logical, arithmetic logics; these operations are structured and coded into the microprocessor of the devices using different programming languages. These devices are sometimes also called computer devices i.e. those devices that can help you perform task accurately and manage your data and information for longest possible time period.

For any computing device a processor is the most important integrated part of the hardware, it is integrated and the logics and code is integrated in the processor.

Processors

A processor is the logic circuitry that responds to and processes the basic instructions that drive a computer. The term processor has generally replaced the term central processing unit (CPU).

A central processing unit or processor is an electronic circuit that can execute computer programs. This term has been in use in the computer industry at least since the early 1960s. The form, design and implementation of CPUs have changed dramatically since the earliest examples, but their fundamental operation has remained much the same.

The processor in a personal computer or embedded in small devices is often called a

microprocessor.A microprocessor incorporates most or all of the functions of a central processing unit

(CPU) on a single integrated circuit. The first microprocessors emerged in the early 1970s and were used for electronic calculators, using binary-coded decimal arithmetic on 4-bit words. Other embedded uses of 4- and 8-bit microprocessors, such as terminals, printers, various kinds of automation etc, followed rather quickly. Affordable 8-bit microprocessors with 16-bit addressing also led to the first general purpose microcomputers in the mid-1970s.

Computer processors were for a long period constructed out of small and medium-scale ICs containing the equivalent of a few to a few hundred transistors. The integration of the whole CPU onto a single VLSI chip therefore greatly reduced the cost of processing capacity. From their humble beginnings, continued increases in microprocessor capacity have rendered other forms of computers almost completely obsolete, with one or more microprocessor as processing element in everything from the smallest embedded systems and handheld devices to the largest mainframes and supercomputers.

COMPUTER

A computer is a machine that manipulates data according to a set of instructions. An electronic or digital device that stores and processes DATA and converts it into Information is known as computer. A machine that accepts input, processes it according to specified rules, and produces output is also referred as a computer.

Computing devices categorization:1. Desktop Computer2. Notebook 3. Tablet Computer4. Handheld5. Mobile or Smart Phone.

Component of the computer:1. Input Devices2. Output Devices3. Storage Units4. Central Processing Unit

Keyboard:In computing, a keyboard is an input device, partially modeled after the typewriter

keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches. A keyboard typically has characters engraved or printed on the keys and each press of a key typically corresponds to a single written symbol. However, to produce some symbols requires pressing and holding several keys simultaneously or in sequence. While most keyboard keys produce letters, numbers or signs, other keys or simultaneous key presses can produce actions or computer commands.

Categorization of keyboard:o Alphanumeric keyso Modifier keyso Numeric keyso Functional keyso Cursor moment keyso Special purpose keys

Monitors: A monitor or display is a piece of electrical equipment which displays images generated

by devices such as computers, without producing a permanent record. The monitor comprises the display device, circuitry, and an enclosure.

Types: CRT (cathode ray tube) LCD (liquid crystal display) TFT (thin film transistor)

Monitor provide the graphical user interface(GUI) for the user as to output the machine language code in user understandable format.

Computer Peripherals:

Computer peripherals are any electronic devices that can be hooked up to a computer other than the standard input-output devices like monitor, keyboard and mouse. Peripheral devices include speakers, microphones, printers, scanners and digital cameras.

Printer:A printer is a peripheral which produces a hard copy of documents stored in electronic

form, usually on physical print media such as paper. Many printers are primarily used as local peripherals, and are attached by a printer cable or, in most newer printers, a USB cable to a computer which serves as a document source.

Categorization of Printers:› Dot matrix› Ink jet› Laser

information(computer)

Print command

Printer ( hard copy)

Scanners:A scanner is a device that optically scans images, printed text, handwriting, or an object,

and converts it to a digital image. Common examples found in offices are variations of the desktop scanner where the document is placed on a glass window for scanning. Hand-held scanners, where the device is moved by hand, have evolved from text scanning "wands" to 3D scanners used for industrial design, reverse engineering, test and measurement, orthotics, gaming and other applications. Mechanically driven scanners that move the document are typically used for large-format documents, where a flatbed design would be impractical.

Digital cameras:A portable device that use for still photography at high resolution is known as digital

cameras. In digital cameras, images can be stored on memory stick and transferred to computer by using cable or disks. Some can crop pictures and perform other elementary image editing. Fundamentally they operate in the same manner as film cameras, typically using a lens with a variable diaphragm to focus light onto an image pickup device.

Projectors:Projectors can be divided in many parts:

Video projector is a device that projects a video signal from computer, home theater system etc.

i. Movie projector is a device that projects moving pictures from a filmstrip. ii. Slide projector is a device that projects a still image with a transparent base.

iii. Overhead projector is a device that projects a transparent image.iv. Opaque projector is a predecessor to the overhead projector.

Hand held devices:

A mobile device is a pocket-sized computing device, typically having a display screen with touch input or a miniature keyboard. In the case of the personal digital assistant (PDA) the input and output are combined into a touch-screen interface. Smart phones and PDAs are popular amongst those who require the assistance and convenience of a conventional computer, in environments where carrying one would not be practical.Different types of hand held devices:

Pen’s /stylus Touch screens Game controller

› Game pad

› Joysticks

Optical input devices: An optical device is a device that creates, manipulates, or measures electromagnetic

radiation. Like ….

Bar code reader› Convert printed image into electronic form› Reads bar code

Image scanner Optical character reader

› To scan text document

Storage media:A storage device may hold information, process information, or both. A device that only

holds information is a recording medium. Devices that process information may either access a separate portable (removable) recording medium or a permanent component to store or retrieve information.

Types: Flash drives

› Pen drives› Capacity range 256 MB-16 GB

Hard disk› Capacity 40 – 500 GB

Smart Cards Reader› Need smart card› Contains small chip› Microprocessor

RIFD:Radio-frequency identification is the use of an object (typically referred to as an RFID

tag) applied to or incorporated into a product, animal, or person for the purpose of identification and tracking using radio waves. Some tags can be read from several meters away and beyond the line of sight of the reader.

Most RFID tags contain at least two parts. One is an integrated circuit for storing and processing information, modulating and demodulating a radio-frequency signal, and other specialized functions. The second is an antenna for receiving and transmitting the signal.

CCTV:Closed-circuit television is the use of video cameras to transmit a signal to a specific

place, on a limited set of monitors.USES:

Crime prevention Hacking and video art Industrial process Traffic monitoring Transport safety Criminal use

Bluetooth Devices:Bluetooth is an open wireless protocol for exchanging data over short distances from

fixed and mobile devices, creating personal area networks (PANs). It was originally conceived as a wireless alternative to RS232 data cables. It can connect several devices, overcoming problems of synchronization. That device is known as Bluetooth devices.

Network devices:List of computer networking devices:

Gateways device sitting at a network node for interfacing with another network that uses different protocols. It works on OSI layers 4to7.

Router is a specialized network device that determines the next network point to which to forward a data packet toward its destination. Unlike a gateway, it cannot interface different protocols. It works on OSI layer 3.

Bridge is a device that connects multiple network segments long thedata link layer. it works on OSI layer2.

Switch is a device that allocates traffic from one network segment to certain lines which connect the segment to another network segment. So unlike a hub a switch splits the network traffic and sends it to different destinations rather than to all systems on the network. It works on OSI layer 2.

Hub connects multiple Ethernet segments together making them act as a single segment. When using a hub, every attached device shares the same broadcast domain and the same collision domain. Therefore, only one computer connected to the hub is able to transmit at a time. Depending on the network topology, the hub provides a basic level 1 OSI Model connection among the network objects (workstations, servers, etc). It provides bandwidth which is shared among all the objects, compared to switches, which provide a dedicated connection between individual nodes. It works on OSI layer1.

Repeater: device to amplify or regenerate digital signals received while setting them from one part of a network into another. It works on OSI layer1.

Daily used electronic devices: Wrist watches i-pod’s Washing machine Microwave's CD/DVD players Dishwasher Air conditioner Fire detector Music systems Refrigerator Play stations Traffic lights

TO CONCLUDE WE CAN SAY THESE DEVICES HAVE BOTH THEIR POSITIVES AND NEGATIVES TO THE MANKIND AND THE WORLD AROUNG

POSITIVES :

CONVINENT, FAST AND SAVE TIME DATA IS ACCESSIBLE ANYWHERE ANYTIME BETTER INFORMATION MANAGEMENT PROVIDE ACCESS TO GLOBAL INFORMATION TRANSFERING INFORMATION FASTER AND ACCURATELY HELPS IMPROVE EFFICIENCY HELPS INCREASE PRODUCTIVITY HELP IN SECURITY – TRANSACTION, CRIME PREVENTION,TRAFFIC MANAGEMENT ENTERTAINMENT

NEGATIVES: OVER DEPEDENCY ON COMPUTING DEVICES HEALTH HAZARDS – RSI , EYE STRAIN, HEART BEAT SLOW ETC HARMFUL RAY CAN LEAD TO IMPOTENCY OVER USE OF THESE DEVICES LEAD TO GLOBAL WARMING