1. Human-Computer Interface

2. Course Syllabus Concepts of Information technology Using the computer and managing files The wide Internet Word Processing Spreadsheets Databases Presentations and multimedia Information and communication

3. Content Administrative Tasks & Organization General concepts Hardware and Software Information Networks The use of IT in everyday life Security Copyright and the Law

4. Administrative Tasks - Organization Purpose: –Facultative not mandatory material –To become familiar with computer technology –Learn to use Office productivity tools Laboratory – each two weeks Exam –“Hands on work” –Written test Try Practic e Labs Exa m Lecture Course

5. Concepts of Information technology What IT means ? –Information Technology = everything linked to using computers, computer technology. Includes the hardware, software and telecommunications. What is Hardware ? –Electronic devices that compose a computer. What is Software ? –Computer programs collections –Instructions that will be executed by a computer and will have affect the hardware

6. Firmware –It’s a “hardware” software component Computers –Machines that process data and information and return results to the users. Computer Science –Special term that refers mostly the theoretical and academic dimensions of using computers. Concepts of Information technology

7. Computer Types They all have a common basic structure. Mainframes Personal computers Network computers and terminals Laptops, personal assistants. They differ in: purpose, speed, cost, storage capacity, processing power and typical users

8. The main components of a computer CPU Memory Storage devices Input devices Output devices Peripheral devices

9. The Von Neumann Machines

10. The Central Processing Unit CPU = Central Processing Unit –Logical Control Unit Controls the machines cycles and execution units: fetch, decode, execute, store. –Arithmetic Logic Unit – execution unit Does all the calculus CPU = Processor +Registers Stores and retrieves data from internal memory

11. The System BUS The system bus connects the various components of a VNA machine. It’s a collection of wires passing electrical signals 8086 has 3 bus types: –Address bus –Data bus – gives the processor bus –Control bus

12. CPU Speed CPU uses the Internal Clock to handle synchronization System Clock = electrical signal on the control bus which alternates between zero and one at a periodic rate

13. CPU Speed The system clock frequency = speed at which the system clock alternates between 0 and 1. CPU Speed = the number of clock cycles occurring each second. Ex: Pentium III ~ 1000 cycles/sec = 1000 Hertz = 1 GHz

14. Memory A device that can store information in any format understood by the CPU.

15. Memory Classifications Localization –External (to CPU) – hard-disk, floppy, external devices –Internal – memory chips. Persistence –Volatile –Non-volatile Operations –ROM – Read Only Memory – non volatile –RAM – Random Access Memory

16. Measuring Memory Allocation units: bits, bytes, Kbytes, Mbytes, Gbytes,Tbytes. 1 bit represents values 0 and 1. 1 bytes = 8 bits = 1 character 1 KB = 1024 bytes 1 MB = 1024 KB = 2 20 bytes 1 GB = 1024 MB

17. Example - Measuring memory A book with 500 pages, ~ 40 lines/page with ~ 40 characters/line gives 500x40x40 = 800.000 characters 800.000 characters = 800.000 bytes = ~ 781 KB =~ 0.76 MB 0.76 MB holds easily on a simple floppy disk.

18. Input Devices Help sending data to the CPU. They convert data from a human understandable format to a format that the CPU understands. Examples: –Mouse / Keyboard –Scanner –Trackball/touchpad –Joystick / light pen –Digital camera / microphone

19. Output Devices Display processing results. They transform CPU language data into human understandable data. Examples: –Monitors / Screens –Printers / plotters. –speakers

20. Graphical Output Devices Monitor – used mostly to display information to the user. Size – diagonal measured (ex. 17 inch) Resolution – measure of the display clarity – measured in pixels. Refresh rate – number of screen redraws/sec – flickering for small values. Color Resolution – the number of coulors a pixel might take.

21. Low Resolution image

22. High resolution image

23. Input/Output Devices They transfer data into both directions – from the human format to the CPU and vice versa. Examples: –Touch Screen –Virtual Reality Head Helmets –Virtual reality gloves.

24. Storage devices Provide data storage space – mainly for long term usage. They differ on terms of cost, capacity and speed. Types: –Floppy, zip disk (1.4 MB; 512 MB) –Data cartdrige/tape (400 MB – 200 GB) –CDROM – CD-R (Write once/read-only), CD-RW, DVD-R and DVD-RW. (650 MB – 4.3 or 9 GB) –Internal/External hard disk (20 GB – 1TB)

25. Software Programs collection running on a computer. Types: –Application software –Operating system software

26. Application software Programs created in order to solve different user problems or handle user requirements. They are used by other programs or directly by the human users. Examples: –Text editors, games, database applications, Web-browsers, communication tools, etc

27. Operating system software Operating System – software that controls the computer hardware and implements services. OS – is automatically launched when the computer is booted. They handle and control all other programs on a computer.

28. OS Structure

29. Operating Systems Interaction with operating systems: –Command language – Unix, MS-DOS –Graphical User Interface – Windows Operating systems examples: –MS-DOS, MacOS, Windows (NT/2000, XP, 2003), Unix, Linux

30. Information Network Computer Network = autonomous and interconnected computer systems collection. LAN – Local Area Network – small size network. WAN – Wide Area Network – large/very large heterogeneous computer network. MAN – Metropolitan Area Network – medium sized computer network (building/region)

31. Computer Networks advantages Resource sharing. –Printers –Processing power (distributed systems) –File sharing. Communication support and media – email, ftp, WWW, etc.

32. Intranet/Internet Intranet - a private network that is contained within an organisation. It may consist of many interlinked local area networks and also use leased lines in the Wide Area Network. Extranet - a private network, that shares part of a business's information or operations with suppliers, vendors, partners, customers, or other businesses from outside

33. Internet Internet – a large scale, global computer network. It is conceived to interconnect any type of computer system from mainframe to PC. Advantages: –Any two computers can communicate irrelevant of their position. –File and message exchange –WWW browsing.