COMPUTE R SYSTE M ORGANISATION Presentation made by:MELJUN CORTES, BSCS,ACS
Index• Evolution of computers – History of computing• Basics of computer and its operation: – Functional Components and their interconnections – Classification of Computers• Software Concepts: – Types of Software - System Software, Utility Software and Application Software;
EVOLUTION OF COMPUTER • The development of the modern day computer was the result of advances in technologies and mans need to quantify. • Let us look at some of the important milestones in the evolution of computers.
ABACUS•The abacus was invented in 3000 BC iBabylonia.•Beads on rods to count and calculate•still widely used in Asia!
Slide Rule 1630based on Napier’s rules forlogarithms used until 1970s
PASCAL’S ADDING MACHINE• In 1642 AD, Blaise Pascal , a Frenchmathematician invented a calculating machinenamed as Adding Machine.• This machine was capable of doing Additionand Subtraction. This device is known as theFirst Calculator of the world.
LEIBNITZ’S CALCULATOR In 1671 AD, Gotfried Leibnitz, a GermanMathematician improved the Adding machine andmade a new machine capable of performingmultiplication and division also.
first stored program - metal cardsfirst computer manufacturingstill in use today!
BABBAGE’S DIFFERENCE ENGINE Charles Babbage was a Britishmathematician. In 1822, he designed a machinecalled Difference Engine. It aimed atcalculating mathematical tables. Since the technology was not so advanced atthat time this machine could not be made.
BABBAGE’S ANALYTICAL ENGINE• In 1833, Charles Babbage designed a machinecalled Analytical Engine. It had almost all theparts of a modern computer. Unfortunately, thismachine could not be built because of lack oftechnology. His designs remained a concept.• His great designs earned him the title of‘FATHER OF COMPUTERS‘.
LADY ADA Lord Byrons daughter, Ada, Countess ofLovelace, suggested to Babbage that he usethe binary system in his machine. She wrote programs for his analyticalengine in 1840, becoming the worlds firstcomputer programmer.
HOLLERITH’S TABULATING MACHINE• Hollerith, a Mathematician, invented a fastcounting machine named TabulatingMachine in 1880.• This machine was used by AmericanDepartment of Census to complete their1880 census data.
MARK I COMPUTER• Howard Aiken of Harvard University in USAjoined hands with the company IBM.• He developed a computer named Mark I in1943.• It could perform mathematical operationsvery fast.• It could perform one operation per second.
ENIAC• The first electronic computer ENIAC wasdeveloped in 1946 by a team lead by ProfessorEckert and Mauchly at the University ofPennsylvania in USA.•Electronic Numerical Integrator andComputer (ENIAC) was very huge and very fast.• It could solve 5000 operations per second.
INTEL 8080 PROCESSOR In 1974 the Intel 8080 processor wasintroduced - it became the basis for the firstpersonal computers.
Definition of Computer Electronic Device Accepts and stores input Manipulates result Outputs results Under direction of stores programs and instructions
Characteristics of Computer• Speed• Accuracy• Diligence : not afflicted to tiredness, monotony, lackof concentration like human beings.• Reliability• Versatility : can work with different types of data likesound, graphics, audio.• Memory
What is Data and Information• Data is raw facts ex: India, 200, 4, Cricket, Wicket• Information is meaningful and arranged form of data ex: India’s score in Cricket is 200 for 4 wickets.
HARDWAREHardware refers to physicalcomponents that can be seen andtouched. E.g. CPU, Memory, I/Odevices.SOFTWARESoftware is a set of programs thatmake the Hardware of thecomputer run.Program is a set of instructions.
FIRMWAREFirmware is like prewritten program that ispermanently stored in read-only memory.BIOS ( Basic Input Output Services )instructions are an example of firmware. LIVEWAREIt is the term generally used for the peopleassociated with and benefited from thecomputer system.
Classification of ComputerSystems• On the basis of Technology •Generations of computers• On the basis of Purpose •General Purpose, special Purpose computers• On The basis of size & Speed •Micro, Mini & Super Computers• On the basis of how it functions •Analog, Digital & Hybrid Computers
Technology Based Classification of Computer Systems Each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly •smaller, •more efficient and •cheaper, •reliable devices. •more powerful
FIRST GENERATIONTIME PERIOD : 1940s-1950s Structure ofTECHNOLOGY USED : Vacuum Tubes a Vaccum TubeSIZE AND SPEED : Huge, taking up entire rooms, SlowspeedLANGUAGE USED : Machine languageCOST : System and UNIVAC working costvery high.OTHER FEATURES : •Used a great deal of electricity. •Generated a lot of heat. ENIAC •Input was based on punched cards and paper tape, and output was displayed on printouts.
SECOND GENERATIONTIME PERIOD : 1950s- 1960sTECHNOLOGY USED : TransistorsSIZE AND SPEED : Lesser size and increased speedLANGUAGE USED : Assembly language and TRANSISITORSlanguages like COBOL and UNIVACFORTRAN 1108COST : Cost decreasedOTHER FEATURES : More efficient and reliable.Though the transistors still generated a great deal of heatthat subjected the computer to damage, it was a vastimprovement over the vacuum tube.Second-generation computers still relied on punched cardsfor input and printouts for output. IBM 1401EXAMPLE : UNIVAC 1108, IBM 1401, CDC 1604
THIRD GENERATIONTIME PERIOD : late 1960s-1970s IBMTECHNOLOGY USED : Integrated Circuit 360/50SIZE AND SPEED : Size Lesser and speed further increasedLANGUAGE USED : Operating System was developed.COST : Cost decreased furtherOTHER FEATURES : Instead of punched cards and printouts, users interacted withthird generation computers through keyboards and monitors and interfaced with an operatingsystem, which allowed the device to run many different applications at one time with a centralprogram that monitored the memory.Computers for the first time became accessible to a mass audience because they were smaller andcheaper than their predecessors.EXAMPLE : IBM-360 series, Honeywell Model 316, Honeywell– 6000
FOURTH GENERATIONTIME PERIOD : 1970s-todayTECHNOLOGY USED : MicroprocessorSIZE AND SPEED : Reduced size andtremendous speed The Macintosh 128K, the firstLANGUAGE USED : High Level Languages Macintosh, was the first commercially successful personallike PASCAL, computer to use images, rather• COBOL, C, C++, JAVA than text, to communicate.COST : Reduced CostOTHER FEATURES : Microprocessors also moved out ofthe realm of desktop computers and into many areas of life asmore and more everyday products began to use microprocessors.•As these small computers became more powerful, they could belinked together to form networks, which eventually led to thedevelopment of the Internet.•Fourth generation computers also saw the development of GUIs, Intel 4004D microprocessorthe mouse and handheld devices.
FIFTH GENERATIONTIME PERIOD : 1990s -todayTECHNOLOGY USED : MicroprocessorSIZE AND SPEED : Reduced size and tremendous speedLANGUAGE USED : Based on Artificial intelligenceCOST : Reduced CostOTHER FEATURES : Fifth generation computing devices, based on artificialintelligence, are still in development, though there are some applications, such as voicerecognition, that are being used today.The goal of fifth-generation computing is to develop devices that respond to naturallanguage input and are capable of learning and self-organization.EXAMPLE : Parallel Inference MachineNote• Artificial Intelligence is the branch of computer science concerned with makingcomputers behave like humans.•Voice Recognition is the field of computer science that deals with designing computer
Size and Speed Based Classification of Computer SystemsThe current classifications of computers place them into four categories: Super Computers, Mainframes, Minicomputers, Microcomputers (Personal Computers)
SUPER COMPUTER The fastest type of computer. Supercomputers are very expensive and are employed for specialized applicationsthat require immense amounts of mathematical calculations. For example, weather forecasting requires a supercomputer. Other uses of supercomputers include animated graphics, , nuclear energyresearch, and petroleum exploration. Characteristics Powerful Expensive Dedicated to one purpose - weather, satellites, military Used by large governments or very large companies Can be used by thousands of people at the same time Very large - fill rooms
Sixteen racks of IBMs Blue Gene/L supercomputer can perform 70.7 trillion calculations per second, making it the fastest machine known so far.
MAINFRAME In the early days of computing, mainframes were huge computers that could fill an entire room or even a whole floor. As the size of computers has decreased while the power has increased, the term mainframe has fallen out of use in favor of enterprise server. Youll still hear the term used, particularly in large companies to describe the huge machines processing millions of transactions every day. Characteristics: Expensive Powerful and fast Is not limited to one job Used by business and small government organizations The main difference between a supercomputer and a mainframe is that a supercomputer channels all its power into executing a few programs as fast as possible, whereas a mainframe uses its power to execute many programs simultaneously.
MINICOMPUTER Another term rarely used anymore, minicomputers fallin between microcomputers (PCs) and mainframes(enterprise servers). Minicomputers are normally referred to as mid-rangeservers now. Characteristics: Smaller than mainframe Can do several jobs at once Can be used by many people at one time Used by small companies
PERSONAL COMPUTER The term microcomputer, also known as personal computer(PC), or a computer that depends on a microprocessor. A microcomputer contains a central processing unit (CPU) ona microchip (the microprocessor), a memory system (read-onlymemory and random access memory), placed on a motherboard. Example: desktop, notebook, laptop, handheld devices. Charcteristics: developed in 1980 designed for single user not very powerful or expensive found in homes
Classification of Computers of On the basis of How It FunctionsThe current classifications ofcomputers place them into fourcategories: Analog Computer Digital Computer Hybrid Computers
Classification of Computers of On the basis of Digital Computers How It FunctionsAnalog DigitalComputers Computers• Operate on continuous data, like • Digital computers work on measuring temp. changes discrete data.• Faster • digital computer can process• Accuracy of an analog computer data with greater accuracy is restricted to the accuracy with which physical quantities can be • We generally use digital sensed and displayed. computers for business and• Specific Purpose computers scientific data processing.
Hybrid Computers• Hybrid computers are computers that comprise features of analog computers and digital computers.• The digital component normally serves as the controller and provides logical operations, while the analog component normally serves as a solver of differential equations.
Purpose Based Classification of Computer Systems General Purpose Special Purpose Computers ComputersThe First Real Computers: Special-purpose computer: 1939: Konrad Zuse Dedicated computers that perform completed the first specific tasks Controlling the temperature and humidity programmable, general- Monitoring your heart rate purpose digital computer Monitoring your house security system
Types of Software Software ( Set of programs that govern the operations of computer ) System Software Application Software ( Software that controls ( Set of programs to carry out operations for a specified internal computer operations ) application ) Operating Language Utilities Packages Customized System Processor Software ( Software ( Software ( perform ( General which converts house utility ( Tailorwhich acts as made HLL progran keeping ) software )an interface software into machinebetween user language ) according and the to user’s hardware ) needs )
Anti Virus e.g., Norton, File Management tools Compression tools Disk Management tools ( Disk Cleanup, DiskFragmentor, Backup)
Language Processors There are three types of Language Processors:• Assembler: This language processor converts the program written in Assembly language into machine language.• Compiler: This converts HLL program into machine language in one go. After the compiler is not needed. It is removed from the memory.Therefore, better memory utilization.• Interpreter: This converts HLL program into machine language by converting and executing it line by line. It must be present In memory every time program is executed. Therefore, unnecessary usage of memory.
Fifth Generation Fourth Generation Third Generation(High Level Language) Second Generation(Assembly Language) First Generation (Machine Language) Low Level Language
Need For OperatingSystem To make computer system convenient to use To use computer hardware in an efficientmanner It decides How to do? What to do? When to do?
Functions of OperatingSystem•Processor Management – Keep track of processor – Decide which job should use the processor – Allocate Processor – Deallocate Processor• File Management – Keep track of files – Decide which job should use the file and for what purpose – Allocate the file for use – Deallocate file after use
Functions of Operating System• Device Management – Keep track of devices – Decide which job should use the processor – Allocate Processor – Deallocate Processor• Memory Management – Keep track of processor – Decide which job should use the processor – Allocate Processor – Deallocate Processor
Types of Operating System• Interactive (GUI)• Time Sharing• Real Time• Distributed
FIRST GENERATION : Machine language i.e. language of 0 and 1SECOND GENERATION : Assembly language Similar to English Uses mnemonics codesTHIRD GENERATION : High Level Language Very close to English E.g. C, C++, Java, VBFOURTH GENERATION : Languages for accessingdatabasesFIFTH GENERATION : Uses a visual or graphical development interface to create sourcelanguage that is usually compiledwith a 3GL or 4GL languagecompiler Used mainly in artificial intelligence research E.g. Prolog, OPS5, and Mercury
B ASIC C OMPONENTS of C OMPUTER S YSTEMSInput/OutputTerminal – Simpler than a PC – Designed strictly for input and output – Has keyboard and screen – Does not have a processor – Connected to computer with telecommunication line – Allows user to key data directly into computer Page 28
B ASIC C OMPONENTS of C OMPUTER S YSTEMSInput/Output• Common input methods: – Magnetic ink character recognition (MICR) – used to process bank checks – Optical character recognition (OCR) – directly scans typed, printed, or handwritten material – Imaging – inputs digital form of documents and photos – Bar code labeling – scans bar codes on packages or products, and reads into computer Page 29
B ASIC C OMPONENTS of C OMPUTER S YSTEMSInput/Output• Common output methods: – Print – output to paper using various types of printers – Computer output microfilm (COM) – microfilm generated for archive copies in small space – Voice response units – computer recognizes input, generates verbal response messages Page 29
B ASIC C OMPONENTS of C OMPUTER S YSTEMSInput/Output st … in tere Of Multimedia – relatively new term for computer input and output in the form of text, graphics, sound, still images, animations, and/or video Page 29
B ASIC C OMPONENTS of C OMPUTER S YSTEMSComputer Memory Secondary Memory
B ASIC C OMPONENTS of C OMPUTER S YSTEMSComputer MemoryMemory – All data flows to and from memory – Divided into cells: • Each has a unique address • Memory cell types: – Byte – stores one character of data – Word – stores two or more characters of data Page 31
B ASIC C OMPONENTS of C OMPUTER S YSTEMSBits and Coding Schemes• Each memory cell is a set of circuits• Each circuit is on or off (represented by 1 or 0)• Each circuit corresponds to a bit (binary digit)• Most computers – 8 bits (circuits) represents a character (byte)• 2 common bit coding schemes used today: – ASCII – EBCDIC Page 32
B ASIC C OMPONENTS of C OMPUTER S YSTEMSArithmetic/Logical Unit Secondary Memory
B ASIC C OMPONENTS of C OMPUTER S YSTEMSArithmetic/Logical Unit• Consists of VLSI circuits on a silicon chip• Carries out: – arithmetic – add, subtract, multiply, divide … – logical operations – comparing two numbers Page 33
B ASIC C OMPONENTS of C OMPUTER S YSTEMSComputer Files(Secondary Memory) Secondary Memory
B ASIC C OMPONENTS OF C OMPUTER S YSTEMSComputer Files (Secondary Memory) • When power is off, everything stored in Main memory is lost • Computer files are used to store data for long term • File storage devices (Secondary Memory) : – Magnetic tape drives, disk drives, floppy drives – Optical CD or DVD drives Page 33
BASIC COMPONENTS OF COMPUTER SYSTEMSComputer Files• Types of DASD – Fixed (hard) drives Figure 2.7 Diagram of a Magnetic Disk Drive Page 34
BASIC COMPONENTS OF COMPUTER SYSTEMSComputer Files (Secondary Memory)• Types of DASD – Removable: • Floppy drives • Zip drives • Newest: portable DASD for PCs – keychain drive