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Chapter 1. An Overview of the Computer System. Web Site: http://bu.edu.eg/staff/abdelwahabalsammak3. Email: abdelwahab.alsammak@feng.bu.edu.eg. Sammaka@gmail.com. This lesson includes the following sections: The Computer System Defined Hardware : The Nuts and Bolts of the Machine
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Chapter 1 • An Overview of the Computer System Web Site: http://bu.edu.eg/staff/abdelwahabalsammak3 Email: abdelwahab.alsammak@feng.bu.edu.eg Sammaka@gmail.com
This lesson includes the following sections: • The Computer System Defined • Hardware:The Nuts and Bolts of the Machine • Software:Bringing the Machine to Life • The Shapes of Computers Today
The Computer System Defined A computer is an electronicdevice used to processdata, converting data into information that is useful to people. A complete computer system includes four distinct parts: • Hardware • Software • Data • User
The Computer System Defined - Hardware: • Types of Hardware • The CPU • Memory • How Memory is Measured • Input and Output Devices • Storage Devices
Hardware: The Nuts and Bolts of the Machine - Types of Hardware • A computer’s hardware devices are categorized as follows: • Processor • Memory • Input and Output (I/O devices) • Storage devices
Hardware: The Nuts and Bolts of the Machine - The CPU • The procedure that transforms raw data into useful information is called processing. This function is divided between the computer’s processor and memory. • The processor is also called the central processing unit (CPU). It manages all devices and performs the actual processing of data. • The CPU consists of one or morechips attached to the computer’s main circuit board (motherboard).
The Central processing Unit (CPU) The central processing unit (CPU) contains electronic circuits that cause processing to occur. The CPU interpretsinstructions to the computer, performs the logical and arithmeticprocessingoperations, and causes the input and output operations to occur. It is considered the “brain” of the computer. It consists of : 1. Control unit (CU) 2. Arithmetic and Logic unit (ALU) 3. Memory unit (MU)
The Central processing Unit (CPU) (cont.) • Control Unit : central system controlsthe flow of data to and from the mainstorage and peripherals. • Arithmetic and Logic Units : This unit performsarithmeticoperations such as addition ,subtraction ,multiplication and division and Logic operations like AND, OR, NOT, XOR. • Memory Unit :Which holds the data in in terms of Program and files. The data stored can be accessed and used whenever required by the CPU for necessary processing.
Hardware: The Nuts and Bolts of the Machine - Memory • Memory also consists of chips attached to the motherboard. • Memoryholdsdata and programinstructions as the CPU works with them. This memory is called Random Access Memory (RAM). • The CPU can find any piece of data in RAM, when it needs it for processing. • RAM is volatile, meaning it holdsdata only when the power is on. When the power is off, RAM's contents are lost.
Hardware: The Nuts and Bolts of the Machine – How Memory is Measured • The smallest usable unit of memory is measured by byte – the amount of memory required to holdonecharacter, like the letter A or the numeral 2. • Computers work with largerchunks of data, measured in multiplebytes, as shown below: Unit Approx. Value Actual Value (bytes) (bytes) Kilobyte (KB) 1,000 1,024 Megabyte (MB) 1,000,000 1,048,576 Gigabyte (GB) 1,000,000,000 1,073,741,824 Terabyte (TB) 1,000,000,000,000 1,099,511,627,776
Hardware: The Nuts and Bolts of the Machine – Input and Output Devices • Input devices acceptdata and instructions from the user or from anothercomputer system. The keyboard and mouse are examples of input devices. • Output devices returnprocesseddataback to the user or to anothercomputer system. The printer and monitor are examples. • Communications devices (such as modems and networkinterfacecards) perform both input and output, allowing computers to shareinformation.
Hardware: The Nuts and Bolts of the Machine - • Storage Devices • Storage devices holddata (Perminant) not currently being used by the CPU. Data is commonly stored on a magnetic or optical disk. Each type of disk uses a special medium for storing data on its surface. • A diskdrive is a device that reads data from and writes data to a disk. Most new computers feature a floppydisk drive, a harddisk drive, and an opticaldisk drive. • The most common optical storage devices are CD-ROM and DVD-ROM drives.
Software: Bringing the Machine to Life • What is Software? • System Software • Application Software
Software: Bringing the Machine to Life – What is Software? • Software is a set of electronic instructions that tells the computer how to do certain tasks. A set of instructions is often called a program. • When a computer is using a particular program, it is said to be running or executing the program. • The two most common types of programs are system software and application software.
Software: Bringing the Machine to Life – System Software • Systemsoftware exists primarily for the computer itself, to helpthe computerperformspecificfunctions. • One major type of system software is the operatingsystem (OS). All computers require an operating system. • The OS tells the computer how to interact with the user and its own devices. • Common operating systems include Windows, the Macintosh OS, OS/2, and UNIX .
Software: Bringing the Machine to Life - Applications • Applicationsoftwaretells the computer how to accomplishtasks the user requires, such as creating a document or editing a graphic image. • Some important kinds of application software are: Word processing programs Spreadsheet software Database management Presentation programs Graphics programs Networking software Web design tools and browsers Internet applications Communications programs Utilities Entertainment and education Multimedia authoring
Computer applications • Computer Database : instead of millions of folders and papers, it stores data and make them easy to access and change it ,allow many users access same data throw database management system .
Computer applications (cont.) • Computer graphics : graphics created by representation and manipulation of image data by a computer . • Examples Used in : • Graphical user interface • Games • Computer animation
Computer applications (cont.) • Image processing : extracting image information . • Examples Used in : • Objects and human Recognition • Detecting manufacture defects • Enhancement of important images • Get effects and analyze it • Medicine - You can diagnose diseases.
Computer applications (cont.) • Computer Networks : connecting computers with each other and exchange data • Example : World wide web
Computer applications (cont.) • Web sites and applications : is a set of related web pages and applications accessed over a network such as the Internet or intranet.
Computer applications (cont.) • Artificial intelligence : is the systems and applications that undergo the humanintelligence , it can be learned and give results with very high accuracy • Such as : • Neural networks • Use learning in prediction and recognition • Genetic algorithms • Used in getting best solution to problem
Computer applications (cont.) • Mobile applications : application software is developed for low-power handheld devices • Examples : • Control computer throw Bluetooth • Mobile games
Computer applications (cont.) • Special purpose Micro systems : systems which designed to serve special purpose • Examples : • ATMmachine system • Banksmicrosystems • Robotics :Robots are controlled by software. • Example: • Control robot throw software from cam
Computer applications (cont.) • Wireless sensor networks : is a networks of agents which connected together to perform a task
The Computer Generations • FirstGeneration Computers (1950's) : Vacuum Tubes (valves), Low speed, Punched Cards Storage, Expensive . 2. Second Generation Computers (1960's) : start of using Transistors, Faster, Smaller, Size, Less Expensive. 3. ThirdGeneration Computers (1970's) : Silicon Chips and IC’s, Main Frame Computers, Magnetic Tape Storage. 4. FourthGeneration (1980's) : Very Large Scale Integration (VLSI), PCs, Large Memory Sizes, Magnetic Disk Storage. 5. FifthGeneration (Late 1990's) : Laptop, Optical Storage, Communication, Higher Speed, High Capacity, inexpensive.
Classification of Computers • According to the purpose of the computer. (b) According to the operation size of computer.
(a) Classification as purpose • General Purpose Computers: designed for general use (PCs, Laptops, . .) 2. Special Purpose Computer : designed to perform specificprocessingtasks. Examples are those found in videogames, cameras, digitalwatches, washingmachines, robots etc.
b) According to size and capabilities The Shapes of Computers Today • Supercomputers • Mainframe Computers • Minicomputers • Microcomputers, or Personal Computers
According to size and capabilities(cont.) • Super computers • These computers are characterized as being the fastest, with very high processing speed, very large size, most powerful. • There are widely used in complex scientific applications like processing geologicaldata, weather data, genetic engineering etc.
The Shapes of Computers Today - Mainframe Computers • Mainframe computers can support hundreds or thousands of users, handling massive amounts of input, output, and storage. • Mainframe computers are used in largeorganizations where manyusers need access to shareddata and programs. • Mainframes are also used as e-commerceservers, handling transactions over the Internet.
The Shapes of Computers Today - Minicomputers • Minicomputers are smaller than mainframes but larger than microcomputers. • Minicomputers usually have multipleterminals. • Minicomputers may be used as • Network servers • Internet servers.
The Shapes of Computers Today – Microcomputers, or Personal Computers • Microcomputers are more commonly known as personacomputers. The term "PC" is applied to IBM-PCs or compatible computers desktopcomputers . • Notebook (laptop) computers are used by people who need the power of a desktop system, but also portability. • HandheldPCs such as PDAs (Personal Digital Assistant) lack the power of a desktop or notebook PC, but offer features for users who need limitedfunctions and smallsize.
lesson 1 review: Essential concepts • Namethe four parts of a computer system. • State the main components of the computer hardware. • Differentiate between computer memory and external storage. • Differentiate between the two main categories of computer software. • Compare the five most common types of computer systems according to size and capability. • Differentiate between the two main categories of computer systems according to purpose of use, giving examples.