Current Affairs 2nd Class

        Alphabet Keys     The alphabet keys are the keys A, B, C......Z. These keys help us to write words and sentences on the computer. In English there are 26 alphabets from A to Z that's why there are 26 alphabet keys on the keyboard. (See Figure 2.5.2)               The major part of the keyboard is covered by alphabet keys and its number is more than other keys. There are ______ alphabet keys on the keyboard. (A) 12                                                                    (B) 26 (C) 104                                                                  (D) 4     Answer: (b) Explanation Correct Option:   (B) 26: The keyboard has 26 alphabet keys. Incorrect Options: (A) 12: Numbers of function keys are there. (C) 104: Is the total number of key.   (D) 4:  Is the number of arrows key.            Zacob wants to write his name on the computer. Which key will he press to type his name? (A) Alphabetical keys                                     (B) Numeric keys (C) Function keys                                             (D) Special keys     Answer: (A) Explanation Correct Option: (A) Your name is written with the help of alphabetic keys. Incorrect Options: (B) Numeric keys : Are used for writing numbers. (C) Function keys : Are used for specific purpose. (D) Special keys : Are used for special purpose.  

  Introduction       Children enjoy playing computer games like 'Prince' where they press the keys of a keyboard to make their game characters move faster, jump over obstacles, etc. Actually Keyboard is a standard input device to enter information into the computer. You must have seen a keyboard in your computer lab. It looks and works like a typewriter. We can write and give instructions on the computer by using the keyboard. A  Keyboard tells the computer what to do.              Keys of the Keyboard If you watch a person playing a musical instrument like a piano or Casio then you will see that person pressing some keys. In the same way, the buttons on the Keyboard of the computer are called keys. Generally, a keyboard has 104 or more keys. A keyboard has different groups of keys such as Alphabet keys. Numeric keys and Function keys. Let us discuss about these different types of keys in detail.            

       Output Devices   Output devices are the part of computer hardware equipment?s that are used to communicate the results of data processing carried out by an information processing system (such as a computer) to the outside world (such as a user). Output devices are the medium of communication between the computer and the user.       Using output devices, you can see results like pictures on the screen, sound or music, printed results on paper, etc. The common output devices are the monitor, speakers, headphones and printers.     These are the examples for Output Devices       Monitor   The monitor shows words, numbers, pictures and movies on the screen.           Speaker  The speakers play sound from the computer.           Plotter   The plotter is a computer printing device for printing graphics.                                                 Headphones  The headphones help us to listen to music and sounds.             Printer   The printer helps us to print our work in the computer on paper. Printers are of different kinds such as daisy-wheel printers, laser printers and dot matrix printers. From the list of output devices given above, the monitor or VDU is the standard output device, without which the computer will not run. The other parts are optional and only provide additional features.               Computer performs many functions. The device which shows the result after the completion of work by computer is called _________device.   (A) Input                                                             (B) Output (C) Operations                                                  (D) Processing     Answer: (B) Explanation Correct Option: (B) Output device shows us the result after completion of work by the computer. Incorrect Options: (A) Input: Input device helps us in feeding the instruction                                                                            (C) Operating: System helps in operating the devices (D) Processing: CPU helps in processing the data.            There are many storage devices that are kept away from the computer and inserted when required .Which one of the following is the storehouse available inside the system unit of a computer? (A)  Hard Disk                                                     (B) Floppy Disk (C)  Compact Disk                                             (D) Pen Drive     Answer: (A) Explanation Correct Option (A) Hard Disk is the storehouse available inside the system unit of a computer Incorrect Options: (B) Floppy Disk:  is more...

      Processing Devices   Just like people follow recipes to make food taste in the same way the CPU uses programs to know what it needs to do. The CPU is the 'brain' of the computer. It is the CPU that understands and executes all our instructions which can either be input/output operations or numerical calculations or logical comparisons. It also coordinates the functions of other units of the computer and ensures that everything functions smoothly.  The CPU has to handle a lot of tasks - Read this. Write that. Display that. Copy that........all at the same time. Therefore, the CPU has got some helping parts. The CPU is made up of three parts, namely the Memory, the ALU (Arithmetic and Logic Unit) and the CU (Control Unit). In smaller micro computers like the PC) (Personal Computer, the ALU and the Control Unit are together and this unit is called the Microprocessor. We will now look into the processing of the computer in detail. (See Figure 2.4.10)     Imagine that you are a CPU. You would follow this program if you were thirsty.         Similar to the program shown above, the CPU inside the computer also performs a series of steps to carry out its tasks with the assistance of its helping parts.          Memory   This part stores the data and information, A computer has memory to store data and information for future use. The Memory is the computer's work area. This is the place where the data and programs get stored before being processed and the place where the results get stored before being sent as output.              Control Unit This part controls all the operations of the computer. The Control Unit interprets the results stored in memory, fetches the data for the next instruction from the memory, and coordinates the activities of ALU, the memory and other devices.          ALU This part performs all the arithmetic and logical operations on data selected from the memory. It performs addition, subtraction, multiplication, division and logical comparisons (such as X>Y) on the data sent to it from memory. Interaction among the different components of the computer.              ALU performs all the arithmetic and logical operations on data selected from the memory. What does ALU stand for? (A) Arithmetic and letter unit                     (B) Arithmetic and logical unit (C) Arithmetic and line unit                          (D) Asynchronous and logical unit     Answer: (B)                 Explanation Correct Option: (B) ALU stands for Arithmetic and Logical Unit. Therefore, more...

        Input Devices     The word 'Input' means to 'put in'. Input devices are those which are used to feed data or instructions into the computer. (See Figure 2.4.2)       Using the input device, we can give information to the computer like numbers, |lords and pictures. You can write on the computer by using a keyboard. Hence, the keyboard is an input device. Other input devices are the mouse, joystick. Microphone, scanner, light pen, tracker ball, etc.     These are the examples for Input Devices         Mouse   The mouse is used to move the pointer on the computer screen and draw pictures in the computer. (See Figure 2.4.3)             Joystick   The joystick is used for playing games on the computer. (See Figure 2.4.4)                Microphone                                                      The microphone records sounds on the computer. (See Figure 2.4.5)             Scanner   The scanner copies pictures and photographs on the computer. (See Figure 2.4.6)             Touch Screen   A touch screen enables one to interact with what is displayed on the screen directly with the hand. (See Figure 2.4.7)           Light Pen   A light pen is a computer input device in the form of a light-sensitive wand used with the monitor of a computer. It allows the user to point to displayed objects or draw on the screen. (See Figure 2.4.8)              Webcam   A webcam is a video capture device connected to a computer. (See Figure 2.4.9) From the given list of input devices, it is important to note that the keyboard is a standard input device, without which a computer will not start. Using the other devices like joystick or scanner with the computer is not compulsory and it is on your choice.                Input devices help us to feed the data into the computer. Which one of the following is an example of an input device? (A) Keyboard                                                     (B) printer (C) Monitor                                                        (D) Speaker     Answer: (A) Explanation        Correct Option: (A) The keyboard is used to type more...

Introductions   When someone puts a question to us, we listen with our ears, think about it with our brain and then reply with our mouth. Computers to work in the same way. Devices which help to enter information into the computer are called Input Devices. For example, we enter words and numbers through the keyboard. The devices which show the result after the computer completes work are called Output Devices. A printer prints the work done on a computer on paper; hence it is an output device. Processing is the work done inside the computer to produce some output based on the information given by the user. In addition, formation can also be saved/stored backed up by using tapes. Let's learn more about them. About    

       Output System     As a result of the processing the information that either the person gets the reservation or is unable to get the reservation is output. The end result is called output. The output may be in the form of a ticket, if   seats are available or a message turning down the request. In case the customer is given reservation, his details are stored on the computer. The information regarding availability of seats is displayed on the display unit. Hence, the VDU becomes the output device. If a ticket is to be issued then it is printed on a printer which is also an output device then this forms the output system of the computer. (See Figure 2.3.6)                To get the solution for a problem, computer has to perform certain actions for example:   Input  computer needs data for processing Processing perform various calculation Output sends the output to output device Which is the correct sequence to get the result? (A) Input-output  processing (B) Outputprocessing input (C) Inputprocessing  Output (D) Processingoutput input       Answer: (c) Explanation Correct Option: (C) Computer works on the basis of I-P-O cycle. In this cycle first function is input then processing and finally the output. Therefore, option (C) is correct. Incorrect Options: (A) Sequence given in option (A) is incorrect. (B) Sequence given in option (B) is incorrect. (D) Sequence given in option (D) is incorrect.        Match the following                        A                                           B 1.  Storage device               i.    Plotter 2.  Print graphs                    ii.   Software 3.   LOGO                             iii.   Floppy disk (A) 1, iii; 2, i; 3, ii                                                (B) 1, ii; 2, i; 3, iii (C) 1, i; 2, ii; 3, iii                                                (D) 1, iii; 2, ii; 3, i     Answer: (a) Explanation Correct Option: (A) Option (A) is matched correctly. Floppy disk is a storage device, plotis a print graphs and LOGO is software. Incorrect Options: (B) Option (B) is matched incorrectly. (C) Option (C) is matched incorrectly. (D) Option (D) is matched incorrectly.      

• The computer, being a machine, does what it is told more...

         Processing       The process in the airline reservation system includes examining the flight number, the date of the journey, the class requested and determining whether seats are available as per the reservation details. This is called processing. This processing s performed by a component of the computer called the microprocessor.        Processing is one of the most important functions of I-P-O cycle. What does processing mean? (A) Deleting data                                              (B) Use the data according to the instructions (C) Copying data                                               (D) Pasting data     Answer: (b) Explanation Correct Option: (B) During processing computer works according to the instructions. Therefore, option (B) is correct. Incorrect Options: (A) Option (A) is incorrect. (C) Option (C) is incorrect. (D) Option (D) is incorrect.          You cannot obtain any output without processing. Which one of the following parts of the computer performs the action of processing? (A) Monitor                                       (B) CPU (C) Mouse                                           (D) Printer     Answer: (b) Explanation Correct Option: (B) CPU (Central Processing Unit) processes all the information given to it. Therefore, option (B) is correct. Incorrect Options: (A) Monitor: is the display unit. (C) Mouse: is an input device that selects programs on the computer. (D) Printer: is an output device.  

     Input System       A person, who wishes to travel from Delhi to Mumbai by air, fills in a reservation form which contains details of the name, age, destination, etc. of the customer. The customer details are the input. The data in the form is entered through the keyboard. Hence, the keyboard becomes the input device and forms a part of the input system.                              Match the following                  A                                                      B 1. Light pen                                        i. Output 2. systemScanner                            ii. Directly write on screen 3.  VDU                                               iii. Input system (A) 1, i; 2, ii; 3, iii                                                (B) 1, ii; 2, iii; 3, i (C) 1, iii; 2, ii; 3, j                                                (D) 1, ii; 2, i; 3, ii     Answer: (B) Explanation  Correct Option: (B) Option (B) is matched correctly. With the help of a light pen you can directly write on the screen. Scanner is an input system and visual display unit (VDU) is an output system. Incorrect Options: (A) Option (A) is mismatched. (C) Option (C) is mismatched. (D) Option (D) is mismatched.          Read the conversation between Stephen and Jennifer. Whose statement is/are correct? Stephen : Advance Input systems understands that man to machine interface provide the utmost in quality and reliability at the lowest cost of ownership. Jennifer : Advance input systems understands the every command given by i.ian and process is very well but it costlier and common man cannot use it.     (A) Statement of Stephen is correct        (B) Statement of Jennifer is correct (C) Both are correct                                        (D) All of them are correct     Answer: (a) Explanation Correct Option: (A) Statement of Stephen is correct. Incorrect Options: (B) Statement of Jennifer is incorrect. (C) Option (C) is incorrect. (D) Option (D) is incorrect.

         Working Principle of a Computer     If you had watched a magic show then you would have seen that the magician puts some colored bits of paper inside his hat, mumbles some magic words and then pulls out a rabbit! And you begin to wonder because what went in did not come out. The computer can perform some magic too. For example, it can add large numbers and make other complex calculations and give you the result in just a few (seconds. Thus many actions of computer appear as magic. Just as a human being can be seen as a combination of body and mind, the same toes for a computer. The computer is a two part system consisting of a body and wind. The body of the computer is the hardware such as CPU, VDU, etc. These are the mechanical and electronic parts which can be seen and touched. The mind of the computer is the software. It consists of commands and instructions. Therefore a computer is a collection of electronic parts (body) with a set of instructions controlling it (mind). Almost all the systems and the machines that we find around us work in the same ray. They accept some Input. These inputs are processed in a specific manner to produce some Output. For example, we take oranges, put them in the juicer, switch I on and finally we get orange juice.   This Input-Process-Output (I-P-O) cycle is represented in the following figure:                I-P-O Cycle   The I-P-O (Input-Process-Output) cycle can be illustrated with the help of an example of adding numbers. Suppose you are asked to add two numbers 40 and 50. When you are told to add these two numbers you perform this addition by the factoring processes: (See Figure 2.3.1)

• First, you hear the two numbers.
• Then you store the numbers in your memory.
• Your brain adds the two numbers.
• Then the result (40 + 50 = 90) is stored in your memory.
• You either speak out the result loudly or write it down, depending on what is required.  

Now let's evaluate the entire procedure in the form of Input-Process-Output cycle. The numbers that you have to add are called input. The method of addition is called process and the final result is called output. Here, the inputs are 40 and 50. The output is 90. Your ear is the input device, the brain is the processing unit and mouth is the output device.     As you know, the computer does not make any mistake. If there are any errors in the result or output, it is mostly because of the human being who is Goring the data. These errors are called Bugs because they can be irritating. Just like real bugs (small more...