1. TOPICS Information Representation Characters and Images
Fundamentals of Digital Computer Design

2. Information Representation
All information must be rendered into binary in order to be stored on a computer.
Besides numbers, almost all applications must store characters and string information.
Images are pervasive in today’s internet world and must be rendered in binary to be handled by internet browsers.

3. Character Representation
ASCII – PC workstations
EBCDIC – IBM Mainframes
Unicode – International Character sets

4. ASCII
ASCII
Expanded name American Standard Code for Information Interchange
Area covered 7-bit coded character set for information interchange
Characteristics/description Specifies coding of space and a set of 94 characters (letters, digits and punctuation or mathematical symbols) suitable for the interchange of basic English language documents. Forms the basis for most computer code sets

5. ASCII

6. EBCDIC
EBCDIC
Expanded name Extended Binary Coded Decimal Interchange Code
Proprietary specification developed by IBM
Characteristics/description A set of national character sets for interchange of documents between IBM mainframes. Most EBCDIC character sets do not contain all of the characters defined in the ASCII code

7. EBCDIC
EBCDIC
Usage Not much used outside of IBM and similar mainframe environments. When transmitting EBCDIC files between systems care needs to be taken to ensure that the systems are set up for the relevant national code set.

8. EBCDIC

9. UNICODE
Unicode can represent all of the world's characters in modern computer use, including technical symbols and special characters used in publishing. Because each Unicode code value is 16 bits wide, it is possible to have separate values for up to 65,536 characters. Unicode-enabled functions are often referred to as "wide-character" functions.

10. UNICODE
Note that the implementation of Unicode in 16-bit values is referred to as UTF-16. For compatibility with 8- and 7-bit environments, UTF-8 and UTF-7 are two transformations of 16-bit Unicode values. For more information, see The Unicode Standard, Version 2.0.