1. Computer Fundamental - ITD13821 Lecture 01 Extra Numbering System

2. Computer Fundamental - ITD13822

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4. 4 Terminology – File Storage  bit – The smallest unit of data in a computer. A bit can take the value of either one or zero. A bit is the binary format in which data is processed by computers.  byte – A unit of measure that is used to describe the size of a data file, the amount of space on a disk or other storage medium, or the amount of data being sent over a network. One byte consists of eight bits of data.  nibble – Half a byte or four bits.  kilobyte (KB) – 1024, or approximately 1000, bytes.  kilobit (Kb) – 1024, or approximately 1000, bits.  megabyte (MB) – (1024 2 =) 1,048,576 bytes, or approximately 1,000,000 bytes.  gigabyte (GB) - (1024 3 =) 1073741824 bytes, or approximately 1,000,000,000 bytes.

5. Computer Fundamental - ITD13825 Terminology - Rate  kilobits per second (kbps) – A measurement of the amount of data transferred over a connection such as a network connection. kbps is a data transfer rate of approximately 1,000 bits per second.  kilobytes per second (kBps) – kBps is a data transfer rate of approximately 1,000 bytes per second.  megabits per second (Mbps) – Mbps is a data transfer rate of approximately 1,000,000 bits or 10 6 kilobits per second.  megabytes per second (MBps) – MBps is a data transfer rate of approximately 1,000,000 bytes or 10 6 kilobytes per second.

6. Computer Fundamental - ITD13826 Terminology Important !  A capital B indicates bytes.  A lower case b indicates bits.  Multipliers greater than one are capitalized and multipliers less than one are lower case. For example: M=1,000,000 and m=0.001

7. Computer Fundamental - ITD13827 Terminology  hertz (Hz) – A unit of frequency measurement. It is the rate of change in the state, or cycle, in a sound wave, alternating current, or other cyclical waveform. Hertz is synonymous with cycles per second, and it is used to describe the speed of a computer microprocessor.  megahertz (MHz) – One million cycles per second. This is a common measurement of the speed of a processing chip.  gigahertz (GHz) – One billion cycles per second. This is a common measurement of the speed of a processing chip.

8. Computer Fundamental - ITD13828 Analog and Digital Systems Analog System  An analog system may have an infinite number of values.  For example, the hands on an analog clock face may show an infinite number of times of the day.

9. Computer Fundamental - ITD13829 Analog and Digital Systems Digital System  An digital system only occupies a fixed number of discrete values.  In binary arithmetic, as used in computers, only two values are allowed. These values are 0 and 1.  Computers and cable modems are examples of digital devices.