Perfect Computer Notes

What is a Fiber Optic Cable? A Fiber Optic cable comes with the technology that uses glass threads called fibers to transmit data as pulses of light. A fiber optic cable consists of a bundle of glass threads, each of which is capable of transmitting messages modulated onto light waves. A Fiber Optic Cable transmits data as pulses of light through tiny tubes of glass. A Fiber Optic cable has a very narow strand of glass like human hair.  What is Bandwidth of a Fiber Cable?  Modern fiber cables can contain up to a thousand fibers in a single cable, with potential bandwidth in the terabytes per second.  Explain Advantages and Disadvantages of Fiber Optic Cable Advantages of fiber Optic Cables Fiber Optic cables are used to create very high speed networks. Fiber Optic cables come with a very high information carrying capacity. Electromagnetic waves cannot disturb the data passing through the Fiber Optic cables. Fiber Optic Cables provide a more reliable and secure data t

Following are the main uses of Communication Technologies: 1. Video Conferencing Video Conferenccing combines the computer communication capabilities with video technologies to conduct an online meeting between two or more distant participants. The participants of a Video Conferencing are normally at different geographical locations within a building like a university campus or within a city at different branch offices of an organizaion in a city. If the communication technology is supported with high speed internet, the participants may in different cities or even in different countries of the world. Uses of Video Conferencing Online Meetings Online Job Interviews Technical Support Distance Learning Requirements for Video Conferencing It requires: A P-IV computer Microphone Speakers Video Cameras Communication Devices Communication Software High Speed Broad Band Internet  2.   Voice Mail Voice Mail works as an answering machine. The caller may l

What is Memory Management? One of the main functions of Operating systems is Memory Management. Memory Management may be defined as the process of managing the optimal use of main memory that is RAM (Random Access Memory). RAM is much faster than hard disk. So RAM is used to store data and instructions temporarily while they are being executed by CPU ( Central Processing Unit or PROCESSOR ). CPU can get data and instructions from RAM much faster that from hard disk. As we know CPU is a very very fast device. It may execute billions of instructions per second. CPU will have to wait for data and instruction from hard disk because getting data from hard disk is very slow. That is why RAM is used. So data and instructions needed for execution are brought into main memory that is RAM first. Now RAM provides data and instructions to CPU rapidly. What is Memory Management and virtual memory management Operating System allocates the required memory are in main memory to program

Why To Use Left Function in Microsoft Excel? The Left function is used to get first N characters from the given text string or the text contained in a cell. Syntax of LEFT Function in Excel LEFT(Text, Number_of_characters) For example, the function LEFT("Normal",3) will return Nor. Syntax of LEFT function with Cell Reference LEFT(CellReference, Number_of_characters) For example, let the cell A2 contains the text Humanity , the function LEFT(A2,5) will return Human . Similarly if Cll A12 contains "England" then Left(A12,5) will give "Engla" that is first five characters of contents of cell A12 from left side. How To Implement LEFT Function in Excel Uses of Excel Functions Left Right in Excel Worksheet    First of all place the cursor in an empty cell next to cell A2, to enter the function. Type = Type the function name LEFT Type the left parenthesis ( Type A2 from keyboard. Type , (that is Comma) Type 5 so that the first 5

What is MAX Function? Learn Practical Use of MAX Function and MIN Function in Excel Worksheets The MAX function is used to get the maximum number from different given numbers in Excel Worksheet. Syntax of MAX Function in Excel MAX(number1,number2,number3,...numberN) For example the function MAX(5,100,35) will return 100, since 100 is largest number of all 5, 100 and 35. Syntax of MAX Function using Cell References MAX(CellRef1:CellRef2) Where CellRef1 is the cell reference of the first cell and CellRef2 is the cell reference of the last cell in the given cell range in Excel Worksheet. What is MIN Function? The MIN function is used to get the minimum number from different given numbers in Excel Worksheet. Syntax of MIN Function in Excel MIN(number1,number2,number3,...numberN) For example the function MIN(5,100,35) will return 5, since 5 is the smallest number of all 5, 100 and 35. Syntax of MIN Function using Cell References MIN(CellRef1:CellRef2) Where Cel

What is the Use of Average Function in Excel?  The Average Function of Excel is used to get the average of the numbers in Excel Worksheet. Syntax of Average Function in Excel    Average(number1, number2, number3, ... number N)   For Example Average(10,15,20) will return 15. Because, Average is calculated by adding all the numbers and then dividing the total by count of the numbers. In above example: Average = (10+15+20) / 3 Which evaluates to 45 / 3 that is 15. Syntax of Average Function in Excel Using Cell references  Average(cellRef1:CellRef2)  where cellRef1 is the cell reference of the first cell and cellRef2 is the cell reference of the last cell in Average function to calculate the required average, in Excel worksheet. Consider the above figure for example: the cells A2, B2, C2, D2 and E2 contains the numbers 5, 15, 30, 40, 50 respectively. How To Implement Average Function in Excel  First of all place the cursor in an empty cell to enter the function. T

Microsoft Excel is very useful in Business and Commerce. Following is a list of the uses of Microsoft Excel in Business and Commerce: 1. Creating Computerized Worksheets Microsoft Excel is a computer software with electronic worksheets. You can easily input, edit, format your business data in computerized worksheets provided by MS Excel. You can manipulate business data easily and efficiently. 2. Recording Business Data Microsoft Excel can be used in business and commerce for recording the daily transaction records of your business. It provides the facility to store and maintain large amounts of records easily and quickly. 3. Use of Excel in Accounts Department a) Accounting System Microsoft Excel can be used to manage the accounting system of your business organization.It records daily transactions of the organization. b) Prepare Accounting Documents Microsoft Excel can be used to prepare balance sheet, trial balance, ledger and other accounting sheets. 4. Maintai