Fundamentals Of Computer Science Lecture - 1 PDF

Fundamentals of Computer Science An-Introduction DR SAMAR HESHAM LECTURE # 1 1 What is a Computer ? A computer is an electronic device that manipulates data (quantifiable facts). It has the ability to store, retrieve, and process dat...

Fundamentals of Computer Science An-Introduction DR SAMAR HESHAM LECTURE # 1 1 What is a Computer ? A computer is an electronic device that manipulates data (quantifiable facts). It has the ability to store, retrieve, and process data to produce information. 2 For What Purpose We Need Information? Support Decision Making Planning Monitoring and Controlling 3 What That Make Computer so Different? Computational Speed: can Storage: virtually perform billions of unlimited, measured in operations per second (measured as a clock GigaBytes, TeraBytes, … speed, Ghz) etc. Generality: unlimited Accuracy: very applications high Connectivity: can be connected to other devices (wired or wireless) 4  Information Technology IT Information technology (IT) is the use of computers to store, retrieve, transmit, and manipulate data or information. IT is a merging of two technologies: ▪ Computing Technology ▪ Communications Technology There are many types of IT, hereafter only some of them: ▪Information System IS … ▪Decision Support System.... ▪Big Data & Big Data Analytics: ▪GIS (Geographical Information the discovery of meaningful System) … information in large data ▪… volumes... ▪Artificial Intelligence. Intelligent software that learns.... 5 Information System An information system is a complete interconnected environment in which raw data - quantifiable facts - is turned into useful information. An information system includes the following parts: ◾ People (Users) ◾ Computer(s): Hardware Software (Programs) ◾ Procedures ◾ Data ▪Communications: Networking Internet 6 Information System People ▪Technical Staff ▪Administrative Staff ▪End Users Procedures ▪The rules or guidelines for people to follow when using software, hardware, and data are procedures. ▪These procedures are typically documented in manuals written by computer specialists. ▪Software and hardware manufacturers provide manuals with their products. These manuals are provided in either printed or electronic form. 7 Computer Hardware Computer Hardware compromise all physical components of the computer, which are: CPU - central processing unit: where decisions are made, computations are performed, and input/output requests are delegated. Main Memory: stores information being processed by the CPU Secondary Memory (Mass Storage): stores data and programs Input devices: Allow people to supply information to computers Output devices: Allow people to receive information from computers. Network connection: Modems, Ethernet interface and Internet connection. 8 Computer Hardware 9 Computer Hardware CPU (Central Processing Unit), “brains” of the Computer, Arithmetic Logical Unit (ALU), performs arithmetic and logical operations. structured as: Control Unit (CU): decodes and executes instructions. Registers that hold data and instructions for CPU to process. Arithmetic and logical operations are performed using binary number system (only 0’s and 1’s). 10 Computer Hardware Microprocessor: A CPU on only one electronic chip (Integrated Circuit). 11 Computer Hardware Memory Stores programs operating system applications data Types RAM - volatile ROM Composed of bits, which are combined into bytes 12 Memory Cells Address Contents 0 -27.2 1 354 2 0.005 3 -26 4 H 5 RTV 001 6...... X 999 75.62 13 Computer Hardware Secondary Storage ▪Semi permanent data-storage capability Magnetic ◦ Hard disk ◦ Floppy disk ◦ Tape Non-magnetic ◦ CD or DVD ◦ memory stick, flash drive ▪Secondary memory usually has much more storage capacity than main memory 14