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Welcome to today's edition of the Computer Kindergarten Newsletter.
Today is Tuesday, May 29, 2001
In this Issue:
Featured Computer Term: Pointing Device
Topic: Deleting Files From an Open Dialog Box
Progressive Learning Series: Adding a Printer
Featured Website: Gas Price Watch
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Today's Featured Computer Term: Pointing Device
A device with which you can control the movement of the pointer to select items on a display screen. Examples of pointing devices include mice, trackballs, joysticks, touchpads, and light pens.
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 four or five, which have different functions depending on what program is running. Some newer mice also include a scroll wheel for scrolling through long documents.
The mouse is one of the great 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:
1. mechanical: 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.
2. optomechanical: Same as a mechanical mouse, but uses optical sensors to detect motion of the ball.
3. optical: 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.
Mice connect to PCs in one of three ways: 1. Serial mice connect directly to an RS-232C serial port or a PS/2 port. This is the simplest type of connection. 2. PS/2 mice connect to a PS/2 port. 3. Cordless mice aren't physically connected at all. Instead they rely on infrared or radio waves to communicate with the computer. Cordless mice are more expensive than both serial and bus mice, but they do eliminate the cord, which can sometimes get in the way.
Trackball
A trackball is a mouse lying on its back. To move the pointer, you rotate the ball with your thumb, your fingers, or the palm of your hand. There are usually one to three buttons next to the ball, which you use just like mouse buttons.
The advantage of trackballs over mice is that the trackball is stationary so it does not require much space to use it. In addition, you can place a trackball on any type of surface, including your lap.
For both these reasons, trackballs are popular pointing devices for portable computers.
Joystick
A lever that moves in all directions and controls the movement of a pointer or some other display symbol. A joystick is similar to a mouse, except that with a mouse the cursor stops moving as soon as you stop moving the mouse. With a joystick, the pointer continues moving in the direction the joystick is pointing. To stop the pointer, you must return the joystick to its upright position. Most joysticks include two buttons called triggers.
Joysticks are used mostly for computer games, but they are also used occasionally for CAD/CAM systems and other applications.
Light Pen
An input device that utilizes a light-sensitive detector to select objects on a display screen. A light pen is similar to a mouse, except that with a light pen you can move the pointer and select objects on the display screen by directly pointing to the objects with the pen.
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Today's Topic: Deleting Files From an Open Dialog Box
Most users rely on the Windows Explorer in "Explorer View" or "Folder View" when deleting files from their system. However, in most applications designed for Windows, there's an easier way, especially if you see a file that needs deleting while performing an Open File or Save As File operation.
Here's how:
1 - While working in your application, select Open or Save As from the file menu
2 - Navigate to the folder that contains the file you wish to delete.
3 - Single click to highlight the file
4 - Press the delete key on the keyboard and click Yes in the resulting box.
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Progressive Learning Series: Adding a Printer
A good way to keep printer costs down and not give up print quality on any type of document printed is to use more than one printer.
While laser printers are preferred for black printing (text documents), the cost of a color laser is still quite high for home or small office use. A lower-priced inkjet printer will do a great job printing the photographs and graphics (watch the prices on replacement cartridges).
Setting up a medium priced laser printer for the text documents and a lower-priced inkjet for the graphics will keep costs down and give high quality output in either format.
Install the new printer as usual. When ready to use the printer, you can now choose it from within the program you're using. Click File from the menu, then Print. In the Name drop down box, choose whichever printer you'd like to use for the current job.
If the new printer doesn't appear in the Name drop-down list, you'll need to add the printer to the list. To do this, use the Add Printer Wizard, which you open by double-clicking Add Printer in the Printers folder (Click Start button, then Settings, then Printers). The wizard asks you a series of questions about your new printer. You may also be asked to insert your Windows disk or a disk that came with your printer.
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Today's Featured Website: Gas Price Watch
Here's a very useful site under the current circumstances. With gaspricewatch.com, you can input your zip code (click on US Gas on the left), choose how far you'd like to travel for gas, and you'll get a list of area stations with lowest prices. The price of heating oil is also included.
You can also become a member and report lowest prices.
www.gaspricewatch.com |
