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                                                             Number System













                      Chapter Profile

                          Number System                                       Decimal to Binary Conversion
                          Binary to Decimal Conversion                        Operations on Binary Numbers


                 Although the words 'data' and 'information' are often used interchangeably, there is an important
                 distinction between the two. In a strict sense, 'data' consists of raw numbers that computers
                 organise to produce information.

                 From an early age, we are introduced to the concept of numbers and counting. Toddlers learn
                 that they can carry two cookies, one in each hand. Kindergarteners start counting by twos and
                 fives. Invariably, we use the Decimal Number System, which is based on 10, most likely because

                 we have 10 fingers. Let us learn more about the number system.
                 Clickipedia



                        ✶ The numerical digits we use today, such as 1, 2, and 3, are based on the Hindu-Arabic
                       numeral system developed over a thousand years ago.

                        ✶ The number 0 is known by various names, including zero, nought, naught, nil, zilch,
                       and zip.


                     NUMBER SYSTEM

                 A number system is simply a method of counting. Many different number systems exist.

                 Consider  a  digital  clock:  it  has  24  hours,  each  hour  composed  of  60  minutes,  and  each
                 minute composed of 60 seconds. When you learnt to count, you used numbers like 1, 2, 3,
                 etc. Similarly, computers use their own number system, known as the Binary Number System.
                 Digital computers represent all kinds of data and information—such as audio, graphics, video,

                 text, and numbers—in binary form. The total number of digits used in a number system is called
                 the base or radix. Therefore, when someone says that they are working with a number system
                 of radix 2, it means base 2, that is, the Binary Number System.  The base is written as a subscript
                 after the number, such as (512) . In this example, the number 10 is written as a subscript to
                                                   10
                 indicate that the number is in the Decimal Number System.

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