In the computer world, the binary number systems the system used. All data is stored and manipulated inside the computer in binary．That is, within the computer all data is reduced to 1's and 0's．This 1'sand 0's are stored in logic circuits called registers, or they are stored in memory. The size of a register or memory location varies according to the kind of computer used.
Today's microcomputers will store either 8 or 16binary digits in each location. Large computers may store as many as 125 binary digits in each location.
We normally enter data into the computer in some number system other than binary because entering data in binary is too time-consuming and too prone to error—too many 1's and 0's．Data is entered into the computer using the decimal, octal, or hexadecimal number systems．Octal and hexadecimal are used most often because they are more closely related to binary than is the decimal system. It Is Important to our understanding of these number system-that we know how they are related one to another.
翻译：
数据和数系
我们大家都知道并理解十进制数系，这是我们每天使用的数系。
在计算机世界中，所用的数系是二进制数系。所有的数据在计算机内部都是以二进制（形式）存储和处理的，就是说，在计算机内部所有数据都归结为1和0这些1和 0存储在称为寄存器的逻辑电路中，或者它们被存储在存储器中，寄存器或存储器单元的大小，按照所用的计算机的种类而变化。
今天的微型计算机在其每个存储单元中，将存储8位或16位二进制数字，大型计算机在其每个字存储单元中可以存储多达125个二进制数字。
我们通常是以某种数系往计算机中输入数据，而不用二进制系，因为以二进制数系输入数据费时间，并且容易出错一一1和0太多，数据在输入计算机时，是用进制、八进制或十六进制数系（进行的）。八进制及十六进制是最常用的，因为它们比十进制数系更接近于二进制数系。理解这些数系是很重要的，因为我们可了解它彼此之间是怎样联系的。