|Ask your group-mates 3 or 4 questions on the text.|
Lesson 2. Keyboard
Read the text.
The term “peripherals” refers to a large class of auxiliary devices that may be connected to a computer. Most peripherals are used either for data storage or for input or output. Although some are virtually essential (there are few computers without keyboards and screens), many peripherals are optional adjuncts to the operation of a computer.
Input devices are the pieces of hardware which allow us to enter information into the computer. The most common are the keyboard and the mouse. We can also interact with a computer by using one of these: a light pen, a scanner, a trackball, a graphics tablet, a game controller or a microphone.
Complete these sentences.
1. This device is enter information into the computer. 2. it
may also function keys and editing keys special purposes. 3. This
is a device the cursor and selecting items on the screen. 4. It usually
two buttons and a wheel. 5. .. .the user active icons or select items
and text. 6. It detecting light from the computer screen and is used by
pointing it directly at the screen display. 7. It the used answer
multi-choice questions and.
Choose one of the input devices given below and describe its functions andfeatures.
A bar code reader; a touchpad on a portable PC; a webcam; a touch screen.
Read and translate the text.
The set of typewriter-like keys that enables you to enter data into a computer is called a keyboard. Computer keyboards are similar to electric- typewriter keyboards but contain additional keys. The keys on computer keyboards are often classified as follows:
Alphanumeric keys represent letters and numbers, as arranged on a typewriter.
Punctuation keys represent comma, period, semicolon, and so on.
Special keys comprise function keys, control keys, arrow keys, Caps Lock key, etc.
Function keys appear at the top of the keyboard and can be programmed to do special tasks.
Cursor control keys include arrow keys that move the insertion point up, down, right and left, and keys such as End, Home, Page Up and Page Down, which are used in word processing to move around a long document.
Dedicated keys are used to issue commands or to produce alternative characters, e.g. the Ctrl key or the Alt key.
A numeric keypad appears to the right of the main keyboard. The Num Lock key is used to switch from numbers to editing keys.
The standard layout of letters, numbers, and punctuation is known as a QWERTY keyboard(pronounced kwer-tee) because the first six keys on the top row of letters spell QWERTY. The arrangement of characters on a QWERTY keyboard was designed in 1868 by Christopher Sholes, the inventor of the typewriter. According to a popular myth, Sholes arranged the keys in their odd fashion to prevent jamming on mechanical typewriters by separating commonly used letter combinations. However, there is no evidence to support this assertion, except that the arrangement does, in fact, inhibit fast typing.
Another keyboard design, which has letters positioned for speed typing, is the Dvorak keyboard. The Dvorak keyboard was designed in the 1930s by August Dvorak, a professor of education, and his brother-in-law, William Dealy. Unlike the traditional QWERTY keyboard, the Dvorak keyboard is designed so that the middle row of keys includes the most common letters. In addition, common letter combinations are positioned in such a way that they can be typed quickly.
There is no standard computer keyboard, although many manufacturers imitate the keyboards of PCs.
Match the descriptions (1-8) with the names of the keys (a-h).
A long key at the bottom of the keyboard.
Each time it is pressed, it produces a blank
It moves the cursor to the beginning of a new
line. It is also used to confirm commands.
It works in combination with other keys. For
example, you press this key and C to copy the
It removes the character to the left of the
cursor or any selected text.
It produces UPPER CASE characters.
It produces UPPER CASE letters, but it
doesn’t affect numbers or symbols.
It moves the cursor horizontally to the right
for a fixed number of spaces (in tabulations and
They are used to move the cursor, as an
alternative to the mouse.
Translate the text in writing.
Computers originally dealt only with letters and numbers as input, so the keyboard is the oldest and most widespread input device. In addition to the basic typewriter arrangement of letters and numbers plus shift key, tab, and so forth, computer keyboards typically contain additional specialized keys. Control (Ctrl) and alternate (Alt) keys are used in conjunction with letter or number keys to issue commands from the keyboard to programs that are running on the computer. For example, Ctrl-C is a key combination often used to “break” or interrupt a program run and return control to the operating system. Function keys (typically ten or twelve) may have frequently used operations assigned to them by various programs one might run. For example, Fl (function key 1) might be used to get on-screen help, F3 to undo the last operation, and F10 to save the file. Cursor keys are used to move the cursor (a blinking line or rectangle indicating the currently active location on the screen) under keyboard control. Additional keys for insert, delete, page up, page down, and other operations help one move around in files during editing. The numeric keypad found on many keyboards is a convenience if many numbers must be entered, because the hand can stay in one location (typically at the right-hand side of the keyboard) rather than having to move back and forth on the top row.
The keyboard communicates with the operating system by issuing an interrupt for every key press. It normally has its own connector to the system unit and so does not occupy an I/O port.
Lesson 3. Mouse
Read and translate the text.
A device that controls the movement of the cursor or pointer on a display screen is a mouse. A mouse is a small object you can roll along a hard, flat surface. Its name is derived from its shape, which looks a bit like a mouse, its connecting wire that one can imagine to be the mouse’s tail, and the fact that one must make it scurry along a surface. As you move the mouse, the pointer on the display screen moves in the same direction. Mice contain at least one button and sometimes as many as three, which have different functions depending on what program is running. Some newer mice also include a scroll wheel for scrolling through long documents.
Invented by Douglas Engelbart of Stanford Research Center in 1963, and pioneered by Xerox in the 1970s, the mouse is one of the greatest breakthroughs in computer ergonomics because it frees the user to a large extent from using the keyboard. In particular, the mouse is important for graphical user interfaces because you can simply point to options and objects and click a mouse button. Such applications are often called point- and-click programs. The mouse is also useful for graphics programs that allow you to draw pictures by using the mouse like a pen, pencil, or paintbrush.
There are three basic types of mice.
A mechanical mouse has a rubber or metal ball on its underside that can roll in all directions. Mechanical sensors within the mouse detect the direction the ball is rolling and move the screen pointer accordingly.
An optomechanical mouse is the same as a mechanical mouse, but uses optical sensors to detect motion of the ball.
An optical mouse uses a laser to detect the mouse’s movement. You must move the mouse along a special mat with a grid so that the optical mechanism has a frame of reference. Optical mice have no mechanical moving parts. They respond more quickly and precisely than mechanical and optomechanical mice, but they are also more expensive.
Do you know what Mighty Mouse, Lisa Mouse and Bus Mouse mean?
The name given to Apple’s first multi-button mouse, was launched in 2005. This was the first mouse manufactured and sold by Apple Computers since the Lisa era in 1983 that contained more than a single button. The Mighty Mouse offers four separate button areas including a touch-sensitive top for both the left and right click, a 360-degree clickable scroll bar, and side squeeze buttons to instantly access the Mac OS X Dashboard or other customizable features. Currently the Mighty Mouse is available in both wired and wireless versions.
Lisa Mouse is the name for the mouse that was distributed with Apple’s first mouse-controlled computer (pre-Macintosh) in 1983. The Lisa Mouse used a steel ball (instead of the rubber ball found in more modern mice), and was rectangular in shape with a raised front panel, and contained a single mouse button.
A Bus mouse is connected to a computer via an expansion board. Another type of mouse was a serial mouse connected to a serial port. Serial mice were easier to install, but the advantage of bus mice was that they do not use up the serial port, so you could use the port for a different device. Bus mice are now obsolete.
Hamster is the name given to a cordless mouse that operates through an infrared connection.
Complete this text about the mouse with verbs from the box:
Click double-click drag grab select move control
A mouse allows you to (1) the cursor and move around the
screen very quickly. Making the same movements with the arrow keys on
the keyboard would take much longer. As you (2) the mouse on your
desk, the pointer on the screen moves in the same direction. The pointer usually looks like an |-bar, an arrow, or a pointing hand, depending on what you are doing.
A mouse has one or more buttons to communicate with the computer. For example, if you want to place the insertion point or choose a
menu option, you just (3) (press and release) on the mouse button, and
the option is chosen.
The mouse is also used to (4) text and items on the screen. You
can highlight text to be deleted, copied or edited in some way.
The mouse is widely used in graphics and design. When you want to move an image, you position the pointer on the object you want to move,
press the mouse button, and (5) the image to a new location on the
screen. Similarly, the mouse is used to change the shape of a graphic
object. For example, if you want to convert a square into a rectangle, you (6) one corner of the square and stretch it into a rectangle.
The mouse is also used to start a program or open a document: you
put the pointer on the file name and (7) on the name — that is, you
rapidly press and release the mouse button twice.