Information is measured in bits, just as length is measured in meters and time is measured in seconds.Of course knowing the amount of information, in bits, is not the same as knowing the information itself, what it means, or what it implies. How is information quantified? information can be communicated by sequences of 0 and 1 values. By using only 0 and 1, we can deal with data from many different types of sources, and not be concerned with what the data means. Bits are simple, having only two possible values. The mathematics used to denote and manipulate single bits is not difficult. It is known as Boolean algebra.If a bit is to be stored or transported, it must have a physical form. Whatever object stores the bit has two distinct states, one of which is interpreted as 0 and the other as 1. A bit is stored by putting the object in one of these states, and when the bit is needed the state of the object is measured. In today’s electronic systems, a bit of information is carried by many objects, all prepared in the same way (or at least that is a convenient way to look at it). Thus in a semiconductor memory a single bit is represented by the presence or absence of perhaps 60,000 electrons (stored on a 10 fF capacitor charged to 1V ). Similarly, a large number of photons are used in radio communication.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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