1. Bits, Bytes, and Words
1.1. Bits - basic unit of information in computing and telecommunication
1.2. Bytes - a unit of digital information in computing and communications
1.3. Words - term for the natural unit of data used by a particular computer design
1.4. Number Bases
1.4.1. Radix
1.4.2. Base
1.5. Binary System
1.5.1. Early computer design was decimal
1.5.2. Binary is base 2 numbering system
1.5.3. Either a 0 (off) or a 1 (on)
1.6. Octal System
1.6.1. Known as base 8 numbering system
1.7. Decimal System
1.7.1. Base 10 numbering system
1.8. Hexadecimal System
1.8.1. Base 16 numbering system
2. ASCII Codes, Unicode
2.1. The Alphanumeric Representation
2.1.1. 3 alphanumeric codes are in common use. -ASCII (American Standard Code for Information Interchange) -Unicode -EBCDIC (Extended Binary Coded Decimal Interchange Code).
2.2. ASCII
2.2.1. standard seven-bit code that was first proposed by the ANSI in 1963, and finalized in 1968 as ANSI Standard X3.4.
2.2.2. visible and invisible symbols
2.2.3. ASCII character set, each binary value between 0 and 127 represents a specific character.
2.3. Keyboard Input
2.3.1. 1. Key (“scan”) codes are converted to ASCII 2. ASCII code sent to host computer 3. Received by the host as a “stream” of data 4. Stored in buffer and being processed
2.4. Unicode
2.4.1. - 16-bit standard - It is a superset of ASCII
2.5. EBCDIC
2.5.1. - Restricted mainly to IBM or IBM compatible mainframes - Conversion software to/from ASCII available - Common in archival data - Character codes differ from ASCII
3. Data, Information and Processing
3.1. Data format
3.1.1. Computer - process data in binary format
3.1.2. Human communication - includes language, sounds, images
4. Information processing cycle
4.1. input --> process --> output
4.2. Data, information, knowledge
4.2.1. Data: unprocessed facts and figures Information: data that has been interpreted Knowledge: information, experience and insight
4.3. Processing - Data coding
4.3.1. Data - encoded by assigning a bit pattern to each character, digit, or multimedia object
4.3.1.1. Character - ASCII
4.3.1.2. Image - JPEG
4.3.1.3. Video - MPEG-2
4.4. Processing - Data Storage and Compression
4.4.1. Reduce the size of data
4.4.2. Lossless - original form Lossy - data degradation, most common in multimedia
4.4.3. Data integrity - security
4.4.3.1. correctness
4.4.3.2. completeness
4.4.3.3. consistency
4.4.3.4. validity
4.4.3.5. compliance