2. HOW DOES A COMPUTER REPRESENT DATA???
By using two unique binary digits 1 and 0 to
represent the two states on and off.
BINARY
DIGIT (BIT)
ELECTRONI
C CHARGE
ELECTRONI
C STATE
I • ON
O • OFF
3. BIT BYTE
A binary digit (1 or 0 )
Represent an electrical
sate (on or off)
Bit 1 represents ON
Bit 0 represents OFF
The smallest of data the
computer can process.
A group of 8 bits (ex:
11110000)
Represent 256 individual
characters(include
digit,letter,punctuation mark
or any symbol in computer).
* The combination of 0s and 1s that represent characters
are defined by patterns called a coding scheme.
4. EXAMPLE :
00110100 represents 4
00110110 represents 6
01000101 represents E
01000110 represents F
00100001 represents !
00101011 represents +
6. WHAT IS CAPACITY???
Capacity is the number of bytes(characters)
can be hold by storage medium.
7. TYPICAL STORAGE AND CAPACITIES
STORAGE CAPACITY
Tape drive A few hundred kilobytes to several
gigabytes
Diskette 1.44 MB
CD - ROM 650 MB – 1GB
Hard disks
External hard disk
Removable hard disk
Up to 4TB or more
Up to 1TB or more
8. DVD and Blu-ray Storage Capacities
Sides Layers DVD Blu-ray
1 1 4.7GB 25GB
1 2 8.5GB 50GB
2 1 9.4GB 50GB
2 2 17GB 100GB