OBJECTIVES  Explain why a computer represents data in the form of binary  Explain the terms related to data storage: bit, byte, character, word  Calculate the number of bits and bytes in a word/s  State the different units of storage  Keywords  Bit Byte  CharacterWord

Why the computer stores data  For processing  Temporarily  using Random Access Memory (RAM)  For later use  permanently  using secondary storage Computers do not store data the way we see it, but in the form of binary digits

Why binary digits?  The computer is an electronic device  The computer is a digital device  Electronic  the computer uses electricity to work  Digital  the use of binary digits to store data

HOW IS DATA STORED?  A computer’s memory is made up of bi-stable devices (two-state) i.e. components can be set in one of two states, represented by a 0 or 1 (called a binary digit). A bit is the smallest unit of storage in a computer.  A byte is made up of 8 bits which is one character (letter, digit, symbol and even a space)

WHAT’S GOING ON?? Hi! Huh??

So if a byte is the amount of storage needed to store one character then a computer with 32,000 bytes of memory will be able to store up to 32,000 characters!

QUESTIONS?? How many bytes are in the following?  Hi!  Have fun!  A  9 How many bits are in the following?  Hi!  Have fun!  A  9

HOW IS DATA STORED?  Location: a unit of storage space in a computer's main memory  Address: A number that is assigned to each location in a computer’s memory data location data location address address  Word: a fixed-sized group of bits that are handled together by the machine.  Word size: The number of bits (in a word) C

Calculations  1 ch = 1 byte = 8 bits Example:  How many bits are in: have fun!  1 ch = 8 bits  9 ch = 8 * 9 = 72 bits

UNITS OF STORAGE: MEANING OF ACRONYMS  BIT- BINARY DIGIT ( 1 or a 0)  KB- KILOBYTE  MB-MEGABYTE  GB- GIGABYTE  TB- TERABYTE

UNITS OF STORAGE  1 CHARACTER = 1 BYTE = 8 BITS  1KB= 1024 BYTES  1MB= 1024KB  1GB= 1024MB  1TB= 1024GB

HOW IS DATA MEASURED? Can you complete the table below? UNITS OF STORAGE  1 GB=  1 byte =  1 MB =  1 TB =  1 character =  1 KB =

Copy and complete. ANSWER THE FOLLOWING QUESTIONS: 1. A number that is assigned to each location in memory is called _________ 2. A kilobyte is equivalent to ____ bytes 3. A unit of storage space in Main Memory is known as a _______ 4. A fixed group of bits that are handled together by the machine is a ______ 5. The number of bits in a word is known as a ____________ 6. A device that exists in one of two states is __________ 7. What do the following acronyms mean? GB, TB, KB, MB 8. Arrange the units of storage in order from highest to lowest: KB, GB, MB, TB, byte