Chapter 8
Fundamentals of
Fundamentals of
Computer Processing
Computer Processing
Computing History
Computing History
ENIAC - 1946
ENIAC - 1946
UNIVAC I
UNIVAC I
– First sold in 1956 to Census Bureau First sold in 1956 to Census Bureau
IBM System 360 Line of Computers
IBM System 360 Line of Computers
– 1960’s 1960’s
– Revolutionized computingRevolutionized computing
1954 -- first computer installed in a business
1954 -- first computer installed in a business
(another UNIVAC I at GE)
Computing History
Computing History
Early 1970s -- minicomputers
Early 1970s -- minicomputers
Late 1970s -- microcomputers (TRS-80,
Late 1970s -- microcomputers (TRS-80,
Commodore PET)
Commodore PET)
IBM PC
IBM PC
Computer Sizes
Computer Sizes
Mainframes
Mainframes
– LargeLarge
– Centrally locatedCentrally located
– Used by large organizationsUsed by large organizations
Minicomputers
Minicomputers
– Mid-sizedMid-sized
– Today’s server market descended from these Today’s server market descended from these machines
Computer Sizes [cont.]
Computer Sizes [cont.]
Microcomputers Microcomputers
– Made possible by microprocessorMade possible by microprocessor
– PC -- used by one person, or by a few people in the same PC -- used by one person, or by a few people in the same
area
Literacy
Literacy
Computer Literacy
Computer Literacy
– Ability to use computing resourcesAbility to use computing resources
Information Literacy
Information Literacy
– Understanding how and why information Understanding how and why information affects the decision-making process
Control Unit
Arithmetic and Logic Unit
Primary Storage Unit
Central Processing Unit (CPU)
The
Computer
Schematic
Input Data Output
Information
Secondary Storage
Processors
Processors
Main unit where processing is performed
Main unit where processing is performed
– Called CPUCalled CPU
– Microcomputer CPUs called microprocessorsMicrocomputer CPUs called microprocessors
Speed
Speed
– Moore’s LawMoore’s Law
Memory
Memory
Main memory
Main memory
– Storage area where both data being processed Storage area where both data being processed and program instructions being executed are and program instructions being executed are
stored stored
Storage (secondary)
Storage (secondary)
– Magnetized coding on the surface of a storage Magnetized coding on the surface of a storage device
Bits and Bytes
Bits and Bytes
One kilobyte (1KB)
One kilobyte (1KB)
– 221010 bytes (1,024) bytes (1,024)
One megabyte (1MB)
One megabyte (1MB)
– 222020 bytes (1,048,576) bytes (1,048,576)
One gigabyte (1GB)
One gigabyte (1GB)
Different Memory Types
Different Memory Types
RAM - Random access memoryRAM - Random access memory
– Computer programs and data are loaded into RAM to Computer programs and data are loaded into RAM to
be executed by the computer processor
be executed by the computer processor
ROM - Read-only memoryROM - Read-only memory
– Information used by the operating system and Information used by the operating system and
processor when the computer is started
processor when the computer is started
DRAM - Dynamic RAMDRAM - Dynamic RAM
– Allows buffering of data and increases efficiency of Allows buffering of data and increases efficiency of
RAM
Different Memory Types
Different Memory Types
(cont.)
(cont.)
SDRAM - Synchronous DRAMSDRAM - Synchronous DRAM
– Runs much faster than most conventional memory Runs much faster than most conventional memory
because it synchronizes its cycles with the
because it synchronizes its cycles with the
processor’s cycles
processor’s cycles
SIMM - Single in-line memory moduleSIMM - Single in-line memory module
– Holds 9 memory chips and transmits 32 bits of data Holds 9 memory chips and transmits 32 bits of data
per cycle
per cycle
DIMM - Dual in-line memory moduleDIMM - Dual in-line memory module – Transmits 64 bits per data cycleTransmits 64 bits per data cycle
Storage Devices
Storage Devices
Tape or disk drive
Tape or disk drive
Sequential storage
Sequential storage
Random storage
Random storage
High Capacity
High Capacity
Removable Disks and their
Removable Disks and their
Storage Capacities
Storage Capacities
3.5 inch floppy disks holds 1.44 MB of data
Zip disk may hold 100MB or 250MB of data
Jaz disk holds 2GB of data
CD disk holds 650MB of data
Input Devices
Input Devices
Keyboards
Keyboards
Microphones
Microphones
Machine-captured data
Machine-captured data
Output Devices
Output Devices
DisplayedDisplayed
– MonitorMonitor
» ResolutionResolution » PixalsPixals
» GUIGUI
– CGA, EGA, VGA, SVGACGA, EGA, VGA, SVGA
PrintedPrinted
– SpeedSpeed – QualityQuality
Printers
Printers
Impact
Nonimpact
Line
Character
Dot
Daisy
Page
Ink
Laser
Multimedia
Multimedia
Use of more than one media at one time
Use of more than one media at one time
– ImageImage – VideoVideo – AudioAudio
Pointing devices
Pointing devices
Speech synthesis
Speech synthesis
Hardware Changes
Hardware Changes
Power compared to price doubles every 18
Power compared to price doubles every 18
months
months
Cultivate new information about computing
Cultivate new information about computing
resources
resources
– Trade journalsTrade journals
Software
Software
Two main types of software -- system and
Two main types of software -- system and
application
application
System
System
– Performs fundamental tasks that all users of a Performs fundamental tasks that all users of a particular computer require
particular computer require
Application
Application
Three Main System
Three Main System
Software Types
Software Types
Operating system
Operating system
– Manages computer’s processesManages computer’s processes » Schedule tasksSchedule tasks
» Manage hardware and software resourcesManage hardware and software resources » Maintain system securityMaintain system security
Three Main System
Three Main System
Software Types(cont.)
Software Types(cont.)
Utilities
Utilities
– Routine that enables the user to perform certain Routine that enables the user to perform certain
basic data processing activities
basic data processing activities – Copy, erase, sort, merge, et ceteraCopy, erase, sort, merge, et cetera
Language translators
Language translators
– Change programmer instructions into computer Change programmer instructions into computer
instructions
System Software Types
System Software Types
(cont.)
(cont.)
Fourth generation languages
Fourth generation languages
– Called 4GLCalled 4GL
– Describes what is to be done by computerDescribes what is to be done by computer
– Does not describe explicitly how it will be doneDoes not describe explicitly how it will be done – DBMSs are related to this areaDBMSs are related to this area
»SQLSQL
»Query languageQuery language
Source Program
Translate
Object
Program Output
Input Data
The Program is Translated Before the Data is Processed
Application Software
Application Software
Prewritten software
Prewritten software
– Standardized by business functionStandardized by business function
– Also called packaged application software and Also called packaged application software and off-the-shelf application software
off-the-shelf application software – AdvantagesAdvantages
Application Software
Application Software
(cont.)
(cont.)
Custom software
Custom software
– Best for unique business operationsBest for unique business operations
– Far less is created today because of wide Far less is created today because of wide availability
availability
Role of User-Friendly
Role of User-Friendly
Software
Software
Businesses need programmers to create
Businesses need programmers to create
applications
applications
– EmployeesEmployees – ConsultantsConsultants– Contracts with other companiesContracts with other companies
Simple intuitive software is user-friendly
Simple intuitive software is user-friendly
Business users have expertise in their areas
Business users have expertise in their areas
Software Change
Software Change
Software changes almost as rapidly as
Software changes almost as rapidly as
hardware
hardware
– IS professionals are routinely contacted IS professionals are routinely contacted concerning system updates
concerning system updates
– Professional societies and conferencesProfessional societies and conferences
Summary
Summary
Hardware
Hardware
– Processor, memory, storageProcessor, memory, storage – Input, manipulation, outputInput, manipulation, output
Software
Software
– SystemsSystems
– ApplicationApplication
