QUIZ

1. Define input and differentiate among the program, command and user response.

Answer:

In computing, an input device is any peripheral (piece of computer hardware equipment) used to provide data and control signals to an information processing system such as a computer or other information appliance. Input and output devices make up the hardware interface between a computer and a scanner or 6DOF controller.

A computer program (also a software program, or just a program) is a sequence of instructions written to perform a specified task for a computer. A computer requires programs to function, typically executing the program's instructions in a central processor. The program has an executable form that the computer can use directly to execute the instructions. The same program in its human-readable source code form, from which executable programs are derived (e.g., compiled), enables a programmer to study and develop its algorithms.

In computing, a command is a directive to a computer program acting as an interpreter of some kind, in order to perform a specific task. Most commonly a command is a directive to some kind of command line interface, such as a shell.

Specifically, the term command is used in imperative computer languages. These languages are called this, because statements in these languages are usually written in a manner similar to the imperative mood used in many natural languages. If one views a statement in an imperative language as being like a sentence in a natural language, then a command is generally like a verb in such a language.

Many programs allow specially formatted arguments, known as flags, which modify the default behaviour of the command, while further arguments describe what the command acts on. Comparing to a natural language: the flags are adverbs, whilst the other arguments are objects.

2.     Identify the keys and buttons commonly found in desktop computer keyboards, and describe how keyboards for mobile computers and devices differ from desktop computer keyboards.

Answer: 

Change / Modify / Reassign the Keys or Buttons of a Keyboard in Windows

Ever want to change the input of the keys / buttons of your keyboard in Windows (keyboard layout)? Or maybe just interchange the input of two keys like the Alt and Ctrl key? Here’s how.
It’s a challenge to find a laptop with the right mix. It has to have the specs you’re looking for, features you want, design that’s acceptable, and must fit your budget. However, sometimes we tend to neglect some of the minor things we should also be looking out for when buying a laptop – which is the keyboard button layout.
Have you ever felt that one of the keys in your keyboard just doesn’t feel to be in the right place? You felt that the Ctrl key shouldn’t be there and should be in the place of the Alt key? Or one of the keys needs to be disabled?

For desktop computers with separate keyboards, when you don’t like the layout or when you find some keys are in an uncomfortable place in the keyboard, it’s easy to change and buy another keyboard.
For laptops or notebooks however, you can’t do that. You’re stuck with how the keys are situated or laid out. So how do we fix that?
Fortunately for Windows users (Windows NT/2000/XP/Vista/ Win 7), you just need to install KeyTweak created by Travis Krumsick. KeyTweak is technically a keyboard remapper which is absolutely free to download and use. You can interchange keys, change the assignment of several keys or change the layout of the whole keyboard if you want.
Using Keytweak is very easy. You can use the manual method where you click any of the keys in the virtual keyboard and reassign it using the dropdown provided.

Or you can use the Full Teach Mode or Half Teach Mode which can be activated through the buttons located at the bottom.


When in Full Teach Mode, just click Begin Teach Mode and then press (1) the key you want to modify and then (2) press the new key it would be assigned to.

When in Half Teach Mode, click Begin Teach Mode and then press the key you want to modify and then manually select the key it would be assigned to.

It’s really very easy to use and once you’re done reassigning keys, you don’t need to run it again as your keyboard will now have the new ones.
Limitations
Keytweak is great but it still has some limitations which I believe it really can’t be blamed for. One major limitation is the FN Key found in laptops can’t be reassigned. If you want the FN key to be reassigned, the BIOS of your laptop needs to be modified (usually through an update).
Keytweak doesn’t also support multiple keys in one keystroke. If you want that, use the Microsoft Keyboard Layout Creator. I found it harder to use though and it can only modify the alphanumeric keys/buttons. You can’t modify the other keys like Tab, Caps, Shift, Ctrl, Alt, Enter, and Backspace buttons.
Keytweak also can’t modify the keyboard for a single application only. The change it makes is global and affects all applications in your operating system.

Mobile computing is a form of human–computer interaction by which a computer is expected to be transported during normal usage. Mobile computing has three aspects: mobile communication, mobile hardware, and mobile software. The first aspect addresses communication issues in ad-hoc and infrastructure networks as well as communication properties, protocols, data formats and concrete technologies. The second aspect is on the hardware, e.g., mobile devices or device components. The third aspect deals with the characteristics and requirements of mobile applications. While keyboard, is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches. Following the decline of punch cards and paper tape, interaction via teletype-style keyboards became the main input device for computers.

Despite the development of alternative input devices, such as the mouse, touchscreen, pen devices, character recognition and voice recognition, the keyboard remains the most commonly used and most versatile device used for direct (human) input into computers.

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 (characters), other keys or simultaneous key presses can produce actions or computer commands.

In normal usage, the keyboard is used to type text and numbers into a word processor, text editor or other program. In a modern computer, the interpretation of key presses is generally left to the software. A computer keyboard distinguishes each physical key from every other and reports all key presses to the controlling software. Keyboards are also used for computer gaming, either with regular keyboards or by using keyboards with special gaming features, which can expedite frequently used keystroke combinations. A keyboard is also used to give commands to the operating system of a computer, such as Windows' Control-Alt-Delete combination, which brings up a task window or shuts down the machine. It is the only way to enter commands on a command-line interface

3.     Describe different mouse types and explain how to use the mouse

Answer:

Different type of computer mouse.

Function of Computer Mouse, Mouses or Mice

And the time finally comes. Different type of computer mouse has been invented to put an end to the complicated commands in the old version of operating system.

Since its arrival the mouse has reduced the frequent use of the computer keyboard but especially has simplified the user to access to various functions.

With this device you can track, drag, select, move files, icons and folders…, draws pictures… navigate all over the applications of your computer.

To facilitate your multiple tasks you can use one of the different types of mice.

The mechanical mouse requires a ball to move the cursor on the screen. To get more efficacies with this type of mice, a flat surface named mouse pads is necessary.

The optomechanical or optical-mechanical mouse is a combination of the optical and the mechanical technologies. It uses a ball but detects the mouse movement optically. It is now the most commonly used with PC.

The optical mouse uses a laser; precisely an optical sensor to help detecting the mouse’s moving. More expensive than the two other types, the optical mouses offer more precision and speed and even can be used on any surface.

To be really useful, the mouse has to be connected to your PC. To transmit data to the computer three types of interfaces can be used:

The RS-232C serial port connects the mouse to the computer through a thin electrical cord using a 9 pin connector.

The PS/2 port do the same as the first interface mentioned but using a 6 pin connector.

The USB interface receives various types of mice through a USB connector. One of these advantages to use the USB mouse is the possibility to plug-and-play (it) in front or in the back of your computer case, when it contains these kinds of port.

One of the most interesting mouse technologies invented is the wireless mouse which relies infrared, radio signals or Bluetooth to communicate with the computer. Using no cord, the wireless mouse contains a transmitter to send information to a receiver itself connected to the computer. The wireless mouse is usable from 2m to 10m of the computer.

The cordless mouse uses the wireless communication technology (via infrared, radio or Bluetooth) to transmit data to the computer. And like the wireless, it doesn’t use any cord.

Other specification to consider about different type of mice is the function of the buttons. Depending on the manufacturer a computer mouse can have 1 to 4 buttons. However the most commonly used is the two mouse buttons of which the primary button is located to the left side of the mouse.

Especially for computer games players, some mice have been built with five or more extensive arrays of buttons which give easily access to various functions.

Finally each of the different type of computer mouses seems more usable with the scroll wheel, very effective with long document pages. As a matter of fact the scroll wheel can be rotated up and down to navigate within a page as the arrows “up and down” buttons on the keyboard.

Sometimes instead of the scroll wheel, a center button or a “rocker” button is designed to the same effects. But they have to be pressed at the top or bottom to achieve the same tasks.

Even though you are using Laptop computer it’s actually easier to navigate with one these different types of computer mouse.

4. Describe various types of touch screens and explain how a touch - sensitive pad work?

Answer: 

A touchscreen is an electronic visual display that can detect the presence and location of a touch within the display area. The term generally refers to touching the display of the device with a finger or hand. Touchscreens can also sense other passive objects, such as a stylus. Touchscreens are common in devices such as all-in-one computers, tablet computers, and smartphones.

The touchscreen has two main attributes. First, it enables one to interact directly with what is displayed, rather than indirectly with a pointer controlled by a mouse or touchpad. Secondly, it lets one do so without requiring any intermediate device that would need to be held in the hand. Such displays can be attached to computers, or to networks as terminals. They also play a prominent role in the design of digital appliances such as the personal

Types of Touch Screens

 

Touch Screen Types

Touch screens appliances are selling like a hot cake now –a - days because of its easy use and availability in various sizes. Any display device with touch screen feature sell as it comes in the market. Although people appreciate and enjoy this amazing new feature yet most of them don’t know about different types of touch screen. Different types of technologies are used in the formation of touch screen. As technology experiments are going on to derive the best devices ever so is the case with touch screen.

Resistive Touch screen

This type of touch screen is made up of three sheets;

·         conductive

·         resistive

·         protective layer

For making the touch screen conductive and resistive layer are place together with a space between. This space allows the current to pass through it when finger press the screen. This current receive the information is then processed into the desired action. The upper layer on the glass is protection layer so that it protects the screen from scratches in case of odd resistance.

Capacitive Touch screen

As the name describe the type of this touch screen. A thin capacitor or electronically charge sheet is placed on the glass. In response to the finger touch some of the charge from the capacitive layer shifts to the finger.
An interesting myth works over here for the functionality of touch screen. You know that capacitor works with electricity then what is the reason it responses to the human touch. Do you remember that electric shock is given to the human heart at the time of heart failure? This is because many electrons are moving in the human cells. When we touch the capacitive screen some of the charge from the screen travel towards the finger and on sheet it decreases.  This reduction in charge sheet processes the application on touch screen.

Surface acoustic Wave Touch screen

This is the more advanced types of touch screen. They are fast and have sharp image. In this touch screen three sheets are used to perform the action;

·         Sending transducer

·         Receiving transducer

·         Reflectors layer

Both transducers are used in making of screen and these transducers enable the screen to sense the outer touch and reflectors help in giving the proper response. This whole mechanism works through the wave transmission. When we touch the screen a wave produced and transfer from one transducer to the receiver where reflectors get the message. This wave travels back to the specific place and perform the action.