1 / 53

Introduction To Computers

Introduction To Computers. What is a computer?. What Is A Computer?. A programmable machine Responds to a specific set of instructions in a well-defined manner. Can execute a prerecorded list of instructions (a program ).

ulysses-mcdaniel
Télécharger la présentation

Introduction To Computers

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction To Computers

  2. What is a computer?

  3. What Is A Computer? • A programmable machine • Responds to a specific set of instructions in a well-defined manner. • Can execute a prerecorded list of instructions (a program) CLR DATA DEF FN DIM END FOR...TO...STEP GET GOSUB GOTO IF..THEN INPUT LET NEXT ON PRINT READ REM STOP WAIT 10 PI = 0: C = 1 20 PI = PI + 4/C + 4/(C + 2) 30 PRINT PI 40 C=C+4: GOTO 20

  4. What Is A Computer? Textbook An electronic device that • Accepts data (raw facts) • Processes that data • Produces meaningful information • Through math / logic • Without human interventionDATA  INFORMATION

  5. Which Computer is Best? • Dell • Gateway • HP/Compaq • IBMVOTE!

  6. Which Computer is Best?

  7. Need A Computer? • Find the cheapest Dell computer • Build it yourself

  8. Which Computer Is Best? • 2002 PC Magazine Reader Survey

  9. Which Computer Is Best? • 2003 PC Magazine Reader Survey

  10. 2004 PC Mag Reader Survey

  11. 2005 PC Mag Reader Survey

  12. 2008

  13. What Do Computers Do? • Computers perform 4 general operations: • Input • Processing (math / logical) • Output • Storage

  14. All of the following are widely used input devices except __ A. keyboard and mouseB. microphone and scannerC. printer and monitorD. digital camera & PC video camera VOTE!

  15. Input Devices • Keyboards • Mouse Others?

  16. Other Input Devices

  17. System Unit

  18. System Unit

  19. ASUS A7N266 • Processor: • AMD Athlon XP1900+ OEM • RAM: • 256MB PC2700 DDR • Video: • ATI Radeon 9100 64MB Retail • Sound, Network • On board • Communications: • US Robotics 56K V90 PCI • CD-RW: • Lite-On LTR-52246S • Monitor: • Samsung 700NF • Hard Drive: • Seagate Barracuda ATA V 60GB • TOTAL: $650

  20. Processor Unit • Consists of two parts: • Central processing unit (CPU) • Main computer memory (ram)

  21. Memory • Main computer memory • Random access memory • RAM • Measured in bytes (chars) • KiloBytes 1000 • MegaBytes 1 million • GigaBytes 1 billion

  22. 1 bit 2 bits 3 bits 4 bits 0 1 00 01 10 11 000 001 010 011 100 101 110 111 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111 Bit Permutations Each additional bit doubles the number of possible permutations

  23. All of the following are widely used output devices except __ A. display devices (screen/monitor)B. speakers and headsetsC. printersD. ports VOTE!

  24. Output Devices • Printers • Impact • Daisy wheel • Dot matrix • Non-impact • Laser • Ink jet

  25. Laser Printer

  26. Output Devices • Display Devices (monitors or screens)

  27. Monitors • CRT vs. LCD • MONOCHROME vs. Color • Pixels • 640 x 480 VGA • 800 x 600 super VGA • 1024 x 768 “ “ • 1280 x 1024 “ “

  28. Pixel

  29. Auxiliary Storage • Storage of data and programs when not stored in main memory

  30. Storage devices • 1. Floppy disks A. Magnetic disks 3. Hard disks • 2. Zip disks

  31. Diskettes • 5 1/4” • 3 1/2” • Double sided, SS • Double or high density

  32. Hard Drives (Fixed Drives) • Capacity measured in megabytes or terabytes • Size to 5TB

  33. Disk, Track, Sector • Track. • A ring on a disk where data can be written. • Sector. • The smallest unit that can be accessed on a disk.

  34. Storage devices • 2. DVDs • B. Optical Disks • 1. CD s

  35. CD-ROM • Compact disk-read only memory • 600 meg • 22K tracks • Software distributed on CD • Multimedia software • CD-recorders available • Read and write to them

  36. Storage devices • C. Tape • D. Miniature Storage Media

  37. Computer Software • -System software • Operating system • Diagnostic • Application software • Word processing • Spreadsheets • Database management • Business payroll, etc. • Games, et. Al.

  38. Windows Version • Graphical user interface (GUI). • Uses graphics and text to communicate with user. (Contrast with DOS prompt). • Windows 3.1, 3.11. • A GUI. • Not an operating system. • DOS is still required. • Windows 98, XP • An operating system. • Includes a GUI.

  39. Communications • Transmission of data over communications channel such as telephone lines

  40. Communications Equipment • Computers process data using digital signals. • Telephone equipment uses an analog signal. • Modem. • Converts the digital signals of a computer to an analog signal and vice versa. • Data can be transferred from one computer to another using the telephone lines.

  41. Internet Service Provider • ISP • provide subscribers with software necessary for communications • Dixie-Net • CrossRoads • Network One

  42. The Internet • The network of worldwide computers. • World wide web (WWW). • Allows users to use text, graphics, video and sound from other web sites on the internet. • Browsers. • Allow users to browse volumes of information from computers around the world. • Netscape navigator, internet explorer.

  43. Networks • LAN • Local Area Network • Computers in Same Buildings or Close Buildings Connected Through Cables.

  44. WAN • WAN (Wide Area Network) • Computers Connected Thorough Communications Channels Such As Telephone Wires, Microwaves, Etc.

  45. Considerations for Purchasing a Computer • Determine what it will be used for. • Choose your software first. • Beware of hidden costs. • Compare purchases alternatives. • Consider the advantages of buying locally and from direct mail order companies.

  46. Purchasing Continued • Look for free software. • Purchase a system compatible with the one you use elsewhere. • Consider an on-site service agreement. • Use a credit card for purchasing your system. • Plan to use the system for at least 3 years.

  47. Installing a Computer System • Allow for adequate work space. • Install computer in a well-designed work area. • Provide adequate lighting. • Install or move a phone near the computer. • Save all paperwork that comes with your system. • Record the serial numbers of all equipment and software. • Keep all shipping containers. • Install in area where temperature and humidity can be maintained.

  48. Computer Viruses • A computer program designed to infect computer systems by copying itself into other computer files. • The virus program spreads when infected files are executed on host and perhaps copied to another system. • Installing an anti-virus program on your computer. • An anti-virus program activates when the computer is turned on.

More Related