1.1 Data Representation Flashcards
What is binary?
Base 2 number system based on the values 0 and 1 only
What is bit?
Abbreviation for binary digit
What is hexadecimal?
A number system based on the value 16, uses 0-9 and A-F
What is a memory dump?
Contents of a computer memory output to a screen or printer
1 KB
1000 bytes
1 MB
One million bytes
1 GB
1 billion bytes
1 TB
1 trillion bytes
1 Petabyte
1 quadrillion bytes
1 Kibibyte (1 KiB)
2^10
1 mebibyte (1MiB)
2^20
1 gibibyte (1GiB)
2^30
1 tebibyte (1TiB)
2^40
1 pebibyte (1 PiB)
2^50
What do you need to interpret results of a memory dump?
Knowledge of computer architecture
What is one’s complement?
Each binary digit in a number is reversed to allow both negative and positive numbers to be represented.
What is two’s complement?
Each binary digit is reversed and add 1 to the LSB to produce another method of representing negative numbers.
What is BCD?
Binary coded decimal, a system that uses 4 bit code to represent each denary digit.
Uses of BCD
Representation of digits on a calculator or clock display.
In cases like accounting, exact values are needed, so BCD is used to store data to prevent significant errors.
ASCII code
American Standard Code for Information Interchange
The standard ASCII code character set has 7 bits, represents letters, number and characters on a standard keyboard.
Unicode
Allows characters to represent all languages of the worlds, supports more operating systems and search engines globally.
