2 Learning Objectives In this, we will discuss : Introduction to ComputerFunctional Units of a ComputerInternal Core Components of a ComputerInput Devices, Output Device and Storage DevicesGeneration of ComputersClassification of ComputersClassification of NetworksVirus and Antivirus
3 Basics of ITData - Data is defined as facts related to people , places, events or things, which can be represented using number and letters.Instruction - Instruction is specifying what must be done to the data.Information - Information is defined as processed data.
4 Basics of ITIntroduction to Computer & Characteristics of a Computer :- 1. Speed 2. Accuracy 3. Permanent Memory 4. No intelligence 5. Diligence
6 Basics of ITASCII ASCII stands for “American Standard Codes for Information Interchange”. This code is available in two versions the 7-bit and 8-bit code.ASCII-7: In the 7-bit code there are three zones bits. ASCII being a 7 bit code, offered 128 (27) different characters. It had 52 binary values for alphabets, both uppercase and lowercase, 10 for numerals and 66 for special characters.
7 Basics of ITASCII-8: In the 8-bit code there are four zones bits. With the 8 bits, it is possible to have 28=256 codes.The ASCII-8 code is used to code two types of information:-One type is the printable characters such as alphabets, digits and special characters.The other set is known as control characters which represent coded information to control the operation of digital computers and are not printed.
9 Basics of ITFunctional Units of a Computer:- 1. Input. 2 Storing 3. Processing 4. Output 5 Controlling
10 Basics of IT STORAGE UNIT INPUT UNIT CONTROL UNIT OUTPUT UNITSTORAGE UNITCONTROL UNITARITHMETIC LOGIC UNIT
11 Basics of IT Input Unit Functions:- Accepts data from outside world. Converts data to computer acceptable form.Supplies data for further processing.Output Unit Functions:-Accepts results in coded formConverts coded form into human form.Gives this to outside world.Storage Unit Functions:-Stores data and instructions for processing.Store intermediate results.Stores final results after processing.
13 Basics of IT Arithmetic Logic Unit Here the actual execution of data takes place during processing. All calculations and comparisons are performed.All data before processing is stored in ALU and then transferred for further processing.All intermediate results are stored in the primary storage. After complete processing the final results are stored in storage unit.The engineering design of ALU tells the type and number of operations required. Almost all ALU’s perform basic operations-addition, subtraction, multiplication and division plus comparisons.
14 Basics of ITThe microprocessor contains the arithmetic logic unit (ALU) and the control unit for a microcomputer. It is connected to memory and I/O by buses which carry information between the units.
15 Basics of IT Control Unit It selects, interprets, and sees over the execution of the programs. It maintains order and directs the operations.It does not process data but only acts as a central nervous system. It manages and coordinates computer system.It issues signals for further processing.
16 Basics of IT Central Processing Unit The Control Unit and the ALU are together called the CPU.It is the brain of a computer.All major calculations and comparisons are made inside the CPU .It also activates and controls the other operations. The major processors are Intel, AMB, Celeron, Cyrix.
17 Basics of IT The most basic components your computer needs to work:- A CPU or Central Processing Unit. Also known as the Processor.RAM or Random Access Memory.Motherboard.Hard Disk
18 Core Components Computer CPU(Central Processing Unit) Also known as the Processor.The CPU is the brain of the computer. All instructions or decisions are done by the CPU.
19 Core Components Computer Memory Also known as, RAM (Random Access Memory).Ram is used by the CPU to read and write data to.After the CPU does it's work it will write the data back to RAM or, if the CPU needs to read data, it will read the data to RAM before processing it.
20 Core Components Computer Motherboard The mother of all components. Most computer components slots into the motherboard.CPU, RAM and PCI (Peripheral Component Interconnect) devices, is plugged into the motherboard.In the next slide, the motherboard is shown at the center-It depicts how the components slots into the motherboard.There are hundreds of different motherboards and models, but they basically do the same thing, connect all components.
21 Motherboard RAM SLOT CPU FAN Transistors & IC’s Processor SLOT Other SLOT
22 Basics of ITHard DiskThe hard disk is where you store your data. All your documents, music files(mp3's), photos, programs and so on.The picture show a hard disk that has been opened. The hard disk is encased in metal to protect the platters and heads. Again, like most components, there are a lot of different types of disk and sizes.
23 Basics of IT Processors IBM, Intel and AMD are the pioneers in the field of microprocessor manufacturing.All these latest computer processor gained immense popularity after the 1980s as there was great development in the field of computers and technology.Intel 4004 was the first ever single-chip 4-bit microprocessor and it was released on November 15, 1971.
24 Basics of ITThe first 8-bit processor was 8008 and it released on April 1, 1972.Processors such as Intel 8080, 8085, 8086, 8088, 80186, and followed in the forthcoming decade.
25 Basics of ITIntel Core is a brand name used for various mid-range to high-end consumer and business microprocessors made by Intel.In general, processors sold as Core are more powerful variants of the same processors marketed as entry-level Celeron and Pentium.Similarly, identically or more capable versions of Core processors are also sold as Xeon processors for the server and workstation market.
26 Basics of ITThe current lineup of Core processors includes the latest Intel Core i7, Intel Core i5, and Intel Core i3, and the older Intel Core 2 Solo,Intel Core 2 Duo, Intel Core 2 Quad, and Intel Core 2 Extreme lines.
27 Basics of IT Desktop Laptop Brand Code-named Cores Fab Date released Core i3Clarkdale Sandy Bridge2 232 nm 32 nmJanuary 2010 February 2011Arrandale Sandy BridgeCore i5Lynnfield Clarkdale Sandy Bridge Sandy Bridge Ivy Bridge Ivy Bridge45 nm 32 nm 32 nm 32 nm 22 nm 22 nmSeptember 2009 January 2010 January 2011 February 2011 April 2012 April 2012Arrandale Sandy Bridge Ivy Bridge2 2 232 nm 32 nm 22 nmJanuary 2010 February 2011 May 2012Core i7Bloomfield Lynnfield Gulftown Sandy Bridge Ivy Bridge45 nm 45 nm 32 nm 32 nm 22 nmNovember 2008 September 2009 July 2010 January 2011 April 2012Clarksfield Arrandale Sandy Bridge Sandy Bridge Ivy Bridge45 nm 32 nm 32 nm 32 nm 22 nmSeptember 2009 January 2010 January 2011 February 2011 May 2012
28 Basics of IT Popular Input Devices 1. Keyboard 2. Mouse 3. Light pen 4. Audio input units 5. Magnetic disks 6. Scanner 7. Tele terminals 8. Joystick 9. Digitizer (graphic tablet) 10. Magnetic tapes and cassettes 11. Floppy and Winchester disks 12. Optical mark reader (OMR) 13. Magnetic ink character reader (MICR)
29 Basics of IT Types of output devices:- Hard copy devices - Hard copy means that the output is in directly usable form, that is, in printing or plotted form. Following hard copy devices are very popular:1.Printers, 2.Plotters, 3. Photographic outputSoft copy devices - Soft copy is in magnetic/audible form that cannot be used directly. These devices do not produce a permanent record. Following soft copy devices are very popular:1.VDU, 2.Liquid crystal display (LCD) used in laptop
31 Basics of IT Generation of Computers:- 1. First Generation Computers (1945 – 1955) - The main component in use were the vacuum tube. Eg. Eniac2. Second Generation Computers (1955 – 1965) -Computers were built using transistors. Eg. IBM 700 SERIES , IBM 1620, IBM 1401.3. Third Generation Computers (1965 – 1970) - Computers were built using Ics. Eg. IBM 360, IBM 370.
32 Basics of IT4.Fourth Generation Computers (1970 ONWARDS) - In this generation LSI and VLSI chips are introduced. Eg. DESK-TOP, LAP-TOP.5. Fifth Generation Computers (1982 ONWARDS ) -Computer are based on artificial intelligence (AI )
33 Basics of IT Classification of Computers:- Microcomputers – Its is a microprocessor. The first microcomputer was built around 8-bit microprocessor chips. Includes PC , Desk Top Computers, Laptop. For example: Zilog Z80, MOS 6502, Intel 8080, MC 6809.Minicomputers – Minicomputers originated in 1960s. Initially these were 8 bit and 12 bit machines but by 1970s almost all minis were transformed into 16 bit machines. eg. MC68000 SeriesMainframes-mainframe computers are generally 32-bit machines. these are suited to big org. to manage high volume application. eg. Cyber Series, Cray Series, Cray X
35 Basics of IT MEMORY UNIT Random Access Memory ( RAM ) Read Only Memory ( ROM )Cache MemoryClock Speed
36 Basics of IT PRIMARY MEMORY/ STORAGE RAM – RANDOM ACCESS MEMORY ROM – READ ONLY MEMORYPROM – PROGRAMMABLE READ ONLY MEMORYEPROM – ERASABLE PRGRAMMABLE READ ONLY MEMORYEEPROM- ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY
37 SECONDARY STORAGE DEVICES Basics of ITSECONDARY STORAGE DEVICESTypes of Secondary Devices:-Direct Access Storage DevicesSequential Access Storage Devices
38 Basics of IT Direct Access Storage Devices (DASD):- It is any secondary storage device which has relatively low access time relative to its capacity.Historically, IBM introduced the term to cover three different device types:disk drivesmagnetic drumsdata cellsThe direct access capability, occasionally and incorrectly called random access (although that term survives when referring to memory or RAM), of those devices stood in contrast to sequential access used in tape drives.
39 Basics of IT Sequential Access Storage Devices (SASD):- It is a class of data storage devices that read their data in sequence.This is in contrast to random access memory (RAM) where data can be accessed in any order.Sequential access devices are usually a form of magnetic memory.While sequential access memory is read in sequence, accesses can still be made to arbitrary locations by "seeking" to the requested location.
40 Basics of IT Generation of Languages:- Machine Language Low Level LanguageHigh Level LanguageFourth Generation Language
41 Basics of IT Machine Language:- Machine code or machine language is a system of impartibly instructions executed directly by computer's central processing unit (CPU).Each instruction performs a very specific task, typically either an operation on a unit of data (in a register or in memory, e.g. add or move), or a jump operation (deciding which instruction executes next, often conditional on the results of a previous instruction).
42 Basics of IT Low-Level Language:- Low-Level programming language is a programming language that provides little or no abstraction from a computer's instruction set architecture.Generally this refers to either machine code or assembly language.The word "low" refers to the small or nonexistent amount of abstraction between the language and machine language; because of this, low-level languages are sometimes described as being "close to the hardware."
43 Basics of IT High Level Language:- A high-level programming language is a programming language with strong abstraction from the details of the computer.In comparison to low-level programming languages, it may use natural language elements, be easier to use, or be from the specification of the program, making the process of developing a program simpler and more understandable with respect to a low-level language.The amount of abstraction provided defines how "high-level" a programming language is
44 Basics of IT Fourth Generation Language:- A fourth-generation programming language (1970s-1990) (abbreviated 4GL) is a programming language or programming environment designed with a specific purpose in mind, such as the development of commercial business software.In the history of computer science, the 4GL followed the 3GL in an upward trend toward higher abstraction and statement power.The 4GL was followed by efforts to define and use a 5GLFourth-generation languages have often been compared to domain-specific programming languages
45 CLASSIFICATION OF SOFTWARE Basics of ITCLASSIFICATION OF SOFTWAREAPPLICATION SOFTWARE MS-WORD , MS-EXCEL, FOXPRO.SYSTEM SOFTWARE - OPERATING SYSTEM (OS), COMPILERS, INTERPRETERS.
46 CLASSIFICATION OF NETWORKS Basics of ITCLASSIFICATION OF NETWORKSLANMANWAN
47 Basics of ITLANLocal area network, generally called LAN’s are privately-owned networks within a single building or campus of up to a few kilometers in size.They are widely used to connect personal computers and workstations in company offices and factories to share resources and exchange information.
48 Basics of ITLAN’s are distinguished from other kinds of networks by three characters:Their sizeTheir transmission technologyTheir topologyLAN often use a transmission technology consisting of a single cable to which all the machines are attached.LAN often uses various types of topologies for example tree topology, bus topology, ring topology.
49 Basics of ITMANA metropolitan area network or MAN is basically a bigger version of a LAN and normally uses similar technology.It might cover a group of nearby corporate offices or a city and might be either private or public.A MAN can support both data and voice, and might even be related to the local cable television network .
50 Basics of ITWANWide area network spans a large geographical area often a country or continent.It contains a collection of machines intended for running user programs.
51 Basics of IT Network Hardware Network Interface Card(NIC):- It provides an interface between the cables and the clients.Hub :-Hub acts as an intermediate between the Server and the Clients.Switches:-Switches are also called as intelligent hubs .Bridges:-Different LAN’s can be connected by devices called bridges , which operate on the data link layer.
52 Basics of ITA computer virus is a computer program that can replicate itself and spread from one computer to another.The term "virus" is also commonly, but erroneously, used to refer to other types of malware, including but not limited to adware and spyware programs that do not have a reproductive ability.
53 Basics of ITMalware includes computer viruses, computer worms, Trojan horses, most rootkits , spyware, dishonest adware and other malicious or unwanted software, including true viruses.Viruses are sometimes confused with worms and Trojan horses, which are technically different.
54 Basics of ITA worm can exploit security vulnerabilities to spread itself automatically to other computers through networks, while a Trojan horse is a program that appears harmless but hides malicious functions.Worms and Trojan horses, like viruses, may harm a computer system's data or performance.Some viruses and other malware have symptoms noticeable to the computer user, but many are surreptitious or simply do nothing to call attention to themselves.
55 Basics of ITAntivirusAntivirus or anti-virus software is software used to prevent, detect and remove malware, such as: Computer viruses, adware, backdoors, malicious BHOs, dialers, fraud tools, hi , malicious LSPs, rootkits, spyware, Trojan horse and worms. Computer security, including protection from social engineering techniques, is commonly offered in products and services of antivirus software companies.
56 Basics of ITThere are several methods which antivirus software can use to identify malware.1.Signature based detection is the most common method:-To identify viruses and other malware, antivirus software compares the contents of a file to a dictionary of virus signatures.Because viruses can embed themselves in existing files, the entire file is searched, not just as a whole, but also in pieces.
57 Basics of IT2. Heuristic-based detection, like malicious activity detection, can be used to identify unknown viruses.3. File emulation is another heuristic approach:-File emulation involves executing a program in a virtual environment and logging what actions the program performs.Depending on the actions logged, the antivirus software can determine if the program is malicious or not and then carry out the appropriate disinfection actions.
58 Basics of IT Hacker Vs Cracker A hacker is a person who is proficient with computers and/or programming to an elite level where they know all of the in's and out's of a system. There is NO illegality involved with being a hacker.A cracker is a hacker who uses their proficiency for personal gains outside of the law. EX: stealing data, changing bank accounts, distributing viruses etc.
59 Basics of ITWhat the hacker does with their knowledge of systems within the definition of the law is what defines them as a hacker vs a cracker.It's then safe to say that all crackers are hackers, but not all hackers are crackers. This is an important distinction.The term cracker and hacker are used interchangeably (albeit incorrectly) largely due to the ignorance of the general populace, especially the media.
60 Basics of IT The major research area of IT are listed below :- Electronic CommerceStrategic IT ManagementEnterprise Resource PlanningSupply Chain ManagementIT Personnel Management : Careers & CompetenciesManagement of the Outsourcing of IT & Other Business FunctionsData mining, Data Modeling and Decision Support SystemsE-GovernmentVirtual Communities & Knowledge Management
61 References Main Reading Books: 1. P. K. Sinha and Priti Sinha , “Computer Fundamentals”, BPB Publications, 2007.2. Alex Leon and Mathews Leon, “Fundamentals of Information Technology”, Leon Techworld, 2007.3. V. Rajaraman, “Introduction to Information Technology”, PHI, 2006.REFERENCES:1. Alex Leon and Mathews Leon, “Introduction to Computers”, Vikas Publishing House,2007.2. Norton Peter, “Introduction to computers”, TMH, 4th Ed., 2006.3. Simon Haykins, “Communication System”, John Wiley & Sons, 2006.4. B. Basaraj, “Digital Fundamentals”, Vikas Publications, 1999.5. 6. V. Rajaraman, “Fundamentals of Computers”, PHI, 5th Ed., 2006.7. David Anfinson and Ken Quamme, “IT Essentials PC Hardware and Software Component on Guide”, Pearson, 3rd Ed., 2008.8. Malvino and Leach, “Digital Principles and Application”, TMH, 1999.9. Ramesh S. Gaonkar, "Microprocessor Architecture Programming and Application with 8085”, PHI, 2001.