Thursday, January 12, 2012


INPUT DEVICES            

Barcode

Lines of different widths and sizes representing data, that when read will determine what the scanned object is. Barcodes are often used to help organize and index information or prices about an object. Barcodes used by the U.S. postal service that helps speed the delivery of mail is another perfect example of how a barcode could be used. In the picture to the right, is an example of what a barcode for an address may look like.
Barcode readerBarcode readers and scanners
barcode reader or scanner, also known as a point of sale (POS) scanner is a hardware device capable of reading a barcode and printing out the details of the product or logging that product into a database. A perfect example of a barcode reader is a super market barcode scanner that reads and logs the price of a product. In the picture to the right, is an example of a Barcode reader from HP.
Today many smart phones with the proper apps are also capable of scanning and reading barcodes.
Barcode Printers
A hardware device capable of printing out adhesive barcodes that can be attached to a product. This helps identify the product or a company keep track of its inventory.


Digital camera

Digital cameracamera that stores the pictures or videoit takes in electronic format instead of to film. There are several features that makedigital cameras a popular choice when compared to film cameras. First, the feature often enjoyed the most is the LCDdisplay on the digital camera. This display allows users to view photos or video after the picture or video has been taken, which means if you take a picture and don't like the results, you can delete it; or if you do like the picture, you can easily show it to other people. Another nice feature with digital cameras is the ability to take dozens, sometimes hundreds of different pictures. In the picture to the right, is a Casio QV-R62, a 6.0 Mega Pixel digital camera used to help illustrate what a digital camera may look like.
Digital cameras have become the camera solution for most users today as the quality of picture they take has greatly improved and as the price has decreased. Many users however are hesitant in buying a digital camera because of the inability of getting their pictures developed. However, there are several solutions in getting your digital pictures developed. For example, there are numerous Internetcompanies capable of developing your pictures and send you your pictures in the mail. In addition, many of the places that develop your standard cameras film now have the ability to develop digital pictures if you bring them your camera, memory stick, or pictures on CD.


Touch screen

iPhone with touch screenA monitor or other flat surface with a sensitive panel directly on the screen that registers the touch of a finger as input. Instead of being touch-sensitive, some touch screens also use beams across the screen to create a grid that is interrupted by the presence of a finger near the screen.
A touch screen allows a user to interact with a device without a mouse or keyboard for input and is often used in a public environment where the user may only need to access general information, such as directions to a room in a building. In the picture to the right, is an example of a smart phone with a touch screen, this phone has no physical keyboard and all data is inputted using a finger.


Fingerprint

1. When referring to computers and security, a fingerprint refers to any trace of information left by someone. Often, if someone has gained unauthorized access to a computer or network, an administrator or security agent may look for any fingerprints left by the attacker, such as IP addresses, host names, etc. This can be compared to a crime scene detective looking for fingerprints at a crime scene.
Microsoft fingerprint scanner2. When referring to computer hardware, afingerprint scanner or fingerprint readeris a hardware device that verifies a user or enters password information by scanning their finger. In the picture to the right, is an example of a fingerprint scanner byMicrosoft. Computers that do not already include a fingerprint scanner can connect devices such as these to their computer USBports.










Gamepad

XBOX 360 Windows Gamepadgamepad is a peripheral device designed to be connected to a computer or console gaming system. It has multiple buttons and may have one or two mini joysticks. A gamepad is used for playing video games of many types, including sports, first-person shooters, role-playing, and others. In the picture to the right, is an example of the XBOX360 controller for Windows and what a Gamepad may look like.
Gamepads are the primary peripheral device used on console gaming systems like the XBox360PlayStation 3 and Nintendo WII. Some portable gaming systems have a gamepad built into the gaming device itself, like the Sony PSP.


Joystick

Logitech Freedom JoystickAn input device that looks similar to a control device you would find on an arcade game at your local arcades. Ajoystick allows an individual to easily move an object in a game such as navigating a plane in a flight simulator. In the picture to the right, is of the Logitech Freedom 2.4 joystick and an example of what a Joystick may look like.


Paddle

Atari game paddle1. More commonly known as a game paddle orgamepad, a paddle is an input device commonly used with games that may contain various buttons used to steer and utilize different options in a game. All console game systems utilize a paddle or gamepad for control. In the picture to the right, is an example of a game paddle used with the Atari 2600.
2. The term paddle may also be used to describe various handheld devices that are capable of controlling a function on a computer or electronic device.


Graphics tablet

Wacom Pen TabletAlternatively referred to as a drawing tablet and pen tablet, a graphics tablet is a highly accurate hardwareinput device that enables an artist to draw or sketch easier than they would be able to do with a standard computer mouse. In the picture to the right, is an example of a Pen Tablet from Wacom and a great example of these devices.



Keyboard

One of the main input devices used on a computer, a PC's keyboardlooks very similar to the keyboards of electric typewriters, with some additional keys. Below is a graphic of the Saitek Gamers' keyboard with indicators pointing to each of the major portions of the keyboard.
Keyboard
Finally, today most users use the QWERTY style keyboards. Below is a graphic illustration of where each of the keys are on a U.S. QWERTY style keyboard.
Qwerty keyboard layout

Microphone

Logitech USB headset with microphoneSometimes abbreviated as mic, a microphoneis a hardware peripheral originally invented by Emile Berliner in 1877 that allows computer users to input audio into their computers. In the picture to the right, is an example of a USBheadset from Logitech with a microphone. A popular solution for computer gaming.

MIDI

Computer MIDI and keyboard MIDI interfaceShort for Musical Instrument Digital Interface,MIDI is a standard for digitally representing and transmitting sounds that was first developed in the 1980s. The MIDI sound is played back through the hardware device or computer either through a synthesized audio sound or a waveform stored on the hardware device or computer. The quality of how MIDI sounds when played back by the hardware device or computer depends upon that device's capability.
Many older computer sound cards will have a MIDI port, as shown in the top right picture. This port allows a musical instrument devices to be connected to the computer, such as a MIDI keyboard or a synthesizer. Before connecting any of these devices to the computer, you will need to purchase a separate cable, which takes the MIDI/Game port connection into the standard 5-pin DIN midi connector or a USB to MIDI converter. If you do not have a MIDI port the most common way today to connect a MIDI device to a computer is to use aUSB to MIDI port cable.


Mouse

Computer mouseA hardware input device that was invented by Douglas Engelbart in 1963, who at the time was working at the Stanford Research Institute, which was a think tank sponsored by Stanford University. The mouseallows an individual to control a pointer in a graphical user interface (GUI). Utilizing a mouse a user has the ability to perform various functions such as opening a program or file and does not require the user to memorize commands, like those used in a text-based command line environment such as MS-DOS. In the picture to the right, is a picture of a Microsoft IntelliMouse and is an example of what a computer mouse may look like.
The Mouse was originally referred to as an X-Y Position Indicator for a Display System. Xerox later applied the mouse to its revolutionary Alto computer system in 1973. However, because of Alto's unfortunate success, it was first widely used in the Apple Lisa computer. Today, a pointing device is found on virtually every computer.


Computer mice
  • Cordless
  • Footmouse
  • Glidepoint
  • IntelliMouse
  • J mouse
  • Joystick
  • Mechanical
  • Optical
  • Touchpad
  • Trackball
  • TrackPoint
  • Wheel mouse
How a mouse may interface with a computer
  • Bluetooth
  • Infrared
  • PS/2 Port
  • Serial Port
  • USB

Remote

1. When referring to a connection a remote connection or to connect remotely is another way of saying remote access.
Remote2. A hardware device that allows a user to control a device or object in another location. For example, the TV remoteallows a person to change the channel, volume, or turn on and off the TV without having to get up and press the buttons on the front of the TV. In the picture to the right, is an example of a remote, the Harmony One Universal Remote from Logitech.

Optical scanner

Flatbed scannerHardware input device that allows a user to take an image or text and convert it into a digital file, allowing the computer to read or display the scanned object. A scanner is commonly connected to a computer USB,FirewireParallel or SCSI port. In the picture to the right, is an example of a flatbed photo scanner, the Epson V300.
Other scanners include: sheetfed scanner, which is a scanner that scans paper fed into it, handheld scanner, which is a scanner that is held and drag over a page to scan it, and acard scanner, which is a small scanner capable of scanning business cards.


Webcam

Computer webcamA camera connected to a computer that allows anyone connected to the Internet to view either a still pictures or motion video of a user or other object. In the picture to the right, is a LogitechQuickCam Express and an example of what a webcam may look like. Today, most webcams are either embedded into the display with laptopcomputers or connected to the USB or Firewireport on the computer.


VR

NASA employee using VRShort for Virtual Reality, VR is a computer-generated artificial environment that allows a user to view, explore, and manipulate the environment. Virtual Reality is commonly manipulated and explored using various input devices such as goggles, headphones, gloves, or a computer. Using these devices a user can browse throughout a virtual world or pickup and manipulate virtual objects. In the picture to the right, is a Nas a employee using a VR system.



POSTED BY:
uneeb AZI


















                 DOT AND CROSS STRUCTURE                   



Dot-and-cross diagrams

You need to be able to draw dot-and-cross diagrams to show the ions in some common ionic compounds.

Sodium chloride, NaCl

Diagram of bonding in sodium chloride. A sodium ion (2,8)+ gives an electron to a chloride ion (2,8,8)-. Both ions have full highest energy levels.
Sodium ions have the formula Na+, while chloride ions have the formula Cl-. You need to show one sodium ion and one chloride ion. In the exam, make sure the dots and crosses are clear, but do not worry about colouring them.

Magnesium oxide, MgO

Diagram of bonding in magnesium oxide. A magnesium ion (2,8)2+ gives two electrons to an oxide ion (2,8)2-. Both ions have full highest energy levels
Magnesium ions have the formula Mg2+, while oxide ions have the formula O2-. You need to show one magnesium ion and one oxide ion.

Calcium chloride, CaCl2

Diagram of bonding in calcium chloride. A calcium ion (2,8,8)2+ gives one electron to a chloride ion (2,8,8)- and another electron to another chloride ion (2,8,8)-. All three ions have full highest energy levels
Calcium ions have the formula Ca2+. Chloride ions have the formula Cl-.
You need to show two chloride ions, because two chloride ions are needed to balance the charge on a calcium ion.
         POSTED BY:MUNEEB QAZI                                  

                 DOT AND CROSS STRUCTURE                   



Dot-and-cross diagrams

You need to be able to draw dot-and-cross diagrams to show the ions in some common ionic compounds.

Sodium chloride, NaCl

Diagram of bonding in sodium chloride. A sodium ion (2,8)+ gives an electron to a chloride ion (2,8,8)-. Both ions have full highest energy levels.
Sodium ions have the formula Na+, while chloride ions have the formula Cl-. You need to show one sodium ion and one chloride ion. In the exam, make sure the dots and crosses are clear, but do not worry about colouring them.

Magnesium oxide, MgO

Diagram of bonding in magnesium oxide. A magnesium ion (2,8)2+ gives two electrons to an oxide ion (2,8)2-. Both ions have full highest energy levels
Magnesium ions have the formula Mg2+, while oxide ions have the formula O2-. You need to show one magnesium ion and one oxide ion.

Calcium chloride, CaCl2

Diagram of bonding in calcium chloride. A calcium ion (2,8,8)2+ gives one electron to a chloride ion (2,8,8)- and another electron to another chloride ion (2,8,8)-. All three ions have full highest energy levels
Calcium ions have the formula Ca2+. Chloride ions have the formula Cl-.
You need to show two chloride ions, because two chloride ions are needed to balance the charge on a calcium ion.
         POSTED BY:MUNEEB QAZI