cs1907

1. cs1907 Computer Techniques 12 Lectures 9 Practicals

2. Jonathan Benson • Room 309 Kane Building • Tel: (021) 4903975 • jpb2@cs.ucc.ie • www.cs.ucc.ie/~jpb2

3. What we will study • Computer Basics • Hardware • Software • Internet & E-mail • Microsoft Word • Microsoft Excel • Microsoft Power Point

4. This Lecture • Define what a computer is. • Look at what they are good for. • What are the components of a computer and what tasks do they perform. • How do these components work. • Look at software

5. What is a computer? • A general purpose programmable device that is capable of calculating and storing results. • An electronic device that performs calculations • These calculations are often performed a very high speeds, much faster than humans. • Computers also may be used to store data. • More recently computers have been endowed with the ability to communicate.

6. A typical computer

7. What are computers good for? • Repetitive tasks: Computers perform thousands of operations a second. • Not so good at more complex tasks such as recognizing faces or detecting sarcasm. • Storage: Huge amounts of data may be stored on a single computer. • Communication: The second revolution in computing. Millions of computers communicate with each other via the Internet.

8. What do computers consist of? • Hardware • A processor for performing calculations. • Some memory for storing the input & results of the calculations. • Some means of communicating with the user in order to receive input and output the results. • Software • Instructions that tell the computer what to do.

9. The Processor

10. The Processor • The speed of the processor is measured in Hertz (Hz). • The speed a processor runs at is an indication of its performance. • Current computers run at speeds measured in Gigahertz (GHz). • 1000 Hz = 1 Megahertz (MHz). • 1000 MHz = 1 Gigahertz (GHz).

11. The Processor • Another indication of the performance is the amount of transistors a chip has • Moore’s Law states that the power of processors will double every 18-24 months. • Gordon Moore was a co-founder of Intel and made the observation in 1965 based on the amount of transistors per chip. • Moore’s Law has held true thus far

12. Moore’s Law

13. Memory • Computer memory is measured in bits and bytes. • A bit is either a 1 or a 0 and is the smallest unit in computing. • A byte consists of 8 bits: e.g. 10001101 • 0000000=0 • 1111111=255

14. Memory • Most processors will have some on board memory used to hold values while it performs calculations. • L1 cache • Fast to access but very expensive. Usually not that large. • L2 cache • Slower to access but less expensive. Larger than the L1 cache. • Older chips don’t have an L2 cache on the actual chip but have it connected via the motherboard. • A good processor should have plenty of each.

15. Memory • Random Access Memory (RAM) • When the space in the L1 and L2 cache is used up the processor must use the RAM. • This comes at a cost. RAM runs at a much slower speed than the processor’s L1 & L2 cache and time is wasted accessing the RAM. • Currently RAM runs about 100 times slower than the processor. • RAM speed has not improved at the same rate as processor speed. • Regardless, more RAM is better than less.

16. RAM

17. Hard Disk • When more memory than the L1, L2 cache and RAM can provide is required by the processor the hard drive can be used. • This is a last resort as it is the slowest method of all and can detriment the performance of the processor. • The hard drive is typically used for general storage rather than as processor memory. Almost all the software running on a computer will reside on the hard drive. • The hard drive consists of many magnetic disks which store information in much the same manner as an audio tape. • The size of hard disks has increased dramatically over the last few years and current disk sizes range from 10 Giga Bytes to 100 Giga Bytes.

18. Other forms of storage • Floppy disk (1.44MB): slowly becoming obsolete due to the small amount of data it is capable of storing and the slow access speed. • CD ROM(650 MB): A ubiquitous feature on modern computers. Sometimes a CD writer is integrated into the device so that a CD may be burned. • DVD(5.2 GB upwards, depending on the format): Much like a CD but with a much higher capacity. DVD burners are starting to become popular for large scale storage. • ZIP Disks (100MB): Replacements for floppy disks. Limited popularity. • Tape (4 - 100 GB): Used to back up large servers. Not generally used outside professional IT circles.

19. Other components • It is common to have specialized components in modern computers that perform specific tasks and reduce the work load on the processor. • Performance advantages can be gained for relatively little cost since processors are great generalists but rarely perform as well as single task components. • Such components are graphic cards and sound cards which excel at processing graphics and sound respectively but don’t do anything else.

20. Other components • Other specialized items give the computer some sort of ability that it does not have on its own. • Typically these devices give the computer communications ability of some sort. • A modem (modulator-demodulator) modulates signals as they are sent or received on a telephone line. • A LAN (local area network) card allows the computer to communicate with others over a small network to which it is connected. • A Wireless LAN card allows the computer to communicate with others via radio signals.

21. The Mother Board • The Mother Board is the glue that holds all the components together • There will be a slot for the processors • Multiple slots for RAM • Multiple slots for devices such as hard, floppy and CD ROM Drives • Multiple slots for various specialist devices such as graphic cards • Multiple ports for connecting peripheral devices

22. Mother Board

23. Peripherals • What are peripheral devices • Peripherals are devices than are outside the box that constitutes the computer. • Monitor, mouse, printer and keyboard are all peripheral devices. • It is also possible to have peripheral hard drives, CD ROMs, DVDs and many other devices.

24. Monitor

25. Software • The software on a computer puts the hardware to use • Software is a set of instructions to the computer • There are two main types of software • System software • Application software

26. System Software • The underlying software on every computer • Concerned with the computer itself • Controls devices • Manages the file system • Consists of two components • The operating system (OS) • Device drivers (to a lesser extent)

27. Operating System • The operating system acts as an interface between the hardware and the user • Interface for running software • Interface for saving and accessing data via the file system • Hides a lot of the underlying details that you don’t really need to know • It also act as an interface between other software and the hardware • Manages resources and coordinates the actions of other software

28. Operating system • Older operating systems have a text based “command line” interface. • Instructions need to be typed in. • Modern systems have a Graphical User Interface (G.U.I.). • The computers resources are represented graphically. • These graphic representations are called icons. • When you move a mouse over an icon and click on it the operating system performs some action. Usually it will open the file or if it is an executable program it will run it. • The operating system we will be using during this course will be Microsoft 2000 and is G.U.I. based.

29. Windows G.U.I.

30. Device Drivers • Device drivers tell the hardware device how to behave. • Specific to an operating system. If you install a new operating system you will also need to install new device drivers. • Changing a device driver may affect the performance of the device (sometimes better, sometimes worse). • E.g. A sound card may not be able to process a new format of sound data correctly. As a result the manufacturer of the device has a new driver written that will allow the sound card to process the new sound format correctly. The user may download and install the new driver from the internet for free.

31. Application Software • Application Software is concerned with the world outside the computer. • Such applications include word processing, spreadsheets, finding information on the internet and communicating via e-mail. • We will be using MS Word, Excel, PowerPoint, Internet Explorer and some e-mail software during this course.

32. When Software goes wrong. • Software is extremely complex • It is impossible to test thoroughly • It is even harder to test software that interacts with other software. • Mistakes are made due to human error or an unforeseen set of circumstances arises that has not been allowed for. • The software may behave in unexpected and undesirable ways in these circumstances. • These mistakes and oversights are called bugs.

33. Bugs • Bugs can be merely irritating or can cause errors or total collapse of the system. • Serious bugs can cause the program to hang (sit there doing nothing, not responding to anything). • You can stop a hanging program using the Task Manager. • Press Ctrl, Alt and Delete simultaneously to open, highlight the offending program by clicking on it in the list of applications and click End Task.

34. Fixing bugs • Bugs, in particular serious bugs, are fixed by the makers of the software. • Patches are made available to download from the internet and install on your computer. • These patches when properly installed should fix the bug for which they were intended. • Application Software users can inform the makers of the existence of a bug also if they wish and hope that there will be a patch available within a reasonable amount of time

35. This Lecture • How to use Microsoft Windows • Using the keyboard and mouse • Dragging and dropping • Highlighting • Opening files and applications • Dealing with open applications • Organizing Files and Folders

36. Using Windows • There are two ways with which to interact with your computer: • Using the Keyboard • Using the Mouse • The easiest way to use a GUI is with a mouse so we will begin with the mouse.

37. Using the mouse • The mouse is a pointing device that moves a pointing cursor about the screen. • There are also two or more buttons on the mouse. A standard mouse has two buttons: • Left button • This is the one you will use the most • Used for opening files and programs • Right button • This usually gives you extra options on a drop down menu such as: • changing the program that a file is usually opened with • Revealing extra information about that file • Allowing you to rename that file

38. Using the Mouse

39. Using the mouse • There are a few types of clicks you can use • Single click • Left button can highlight files and programs • Left button can open files and program using the start menu • Left button can select options on applications • Right button can activate drop down menu • Double click • Used to open files and programs when using the left button • Click and hold • This is used to select and drag icons or for selecting blocks of text.

40. Dragging and dropping • Click and hold to drag an object • Can be used to move a file to a different location in the file system • Can be used as a quick way of making a shortcut or adding a program to the Start menu • Can be used in conjunction with the Ctrl button • This makes a copy rather than moving the file to a new location

41. Highlighting • You can highlight both text and files • To highlight text you can click and drag the cursor to highlight the required text. • To highlight a file or program simply single right click with the mouse. • You can use the shift button in order to highlight large areas of files and text • Click where you wish to start • Hold shift • Click where you wish to finish • You can use the control button to select non-consecutive items • Simply hold Ctrl and click the files you wish to select

42. Using the Keyboard • There are some different keys on a computer compared to a type writer. • These may behave differently depending on the application that is currently running. • Caps Lock toggles between uppercase (Capital) and lowercase letters. • Arrow Keys can be used to move about in certain applications.

43. Using the Keyboard

44. Using the Keyboard • It is possible to use the keyboard to run programs • Combinations of keys can do certain tasks • Sometimes these are called hotkeys • It takes time to learn how to do this effectively • When you finally learn how to use hotkeys you can save a lot of time. • Some applications are designed for mouse only use. • As an example of using the keyboard rather than the mouse press the windows button near the space bar to activate the start menu and navigate through the options with the arrow keys and then select your desired option by hitting return.

45. The Windows Desktop • After starting you computer and it has completed booting up you can see the windows desktop environment. • You should be able to see icons representing shortcuts to applications. You can left click on these shortcuts to open applications and files. • On the bottom of the screen you will see the taskbar. On the far left is the start button which gives you a popup menu when you left click it. Some of these menu options have a small triangle on their right which indicates that it contains a submenu. Left click on the option you wish to activate.

46. The Windows Desktop & Start Menu

47. The Windows Desktop • On the right hand side of the taskbar you will find icons that represent system related applications. • These applications typically include the sound volume, date and time, anti-virus software and network connection. • Interfaces to these applications can be activated by clicking on them.

48. The Windows Desktop

49. Opening a program/application • A program can be opened in a number of ways • You can use the Start menu • Click on the start menu • Move the cursor over Programs • Move the cursor over the program you wish to open and double left click the mouse on it. • You can use a desktop or taskbar shortcut. • Simply double click on the appropriate icon

50. Opening a program/application • You can explore the file system on your computer until you find the program you wish to open and then left click on it to open. • You cannot find some programs such as Word this way as it is often built into the operating system. • If you do not wish to have a particular program on the start menu or as a shortcut then you must use this method • You can use the run option in the start menu if you know what the name of the program is (this can be problematic).