Computer Tutorial

Sound cards:-

                                      allow computers to produce sound like music and voice. The older sound cards were 8 bit then 16 bit then 32 bit. Though the human ear can't distinguish the fine difference between sounds produced by the more powerful sound card they allow for more complex music and music production

Modem:-

                    A modem is used to translate information transferred through telephone lines, cable or line-of-site wireless. The term stands for modulate and demodulate which changes the signal from digital, which computers use, to analog, which telephones use and then back again. Digital modems transfer digital information directly without changing to analog.
Modems are measured by the speed that the information is transferred. The measuring tool is called the baud rate. Originally modems worked at speeds below 2400 baud but today analog speeds of 56,000 are standard. Cable, wireless or digital subscriber lines can transfer information much faster with rates of 300,000 baud and up.
Modems also use Error Correction which corrects for transmission errors by constantly checking whether the information was received properly or not and compression which allows for faster data transfer rates. Information is transferred in packets. Each packet is checked for errors and is re-sent if there is an error.
Anyone who has used the Internet has noticed that at times the information travels at different speeds. Depending on the amount of information that is being transferred, the information will arrive at it's destination at different times. The amount of information that can travel through a line is limited. This limit is called bandwidth.
There are many more variables involved in communication technology using computers, much of which is covered in the section on the Internet.

Printers:-

                   The printer takes the information on your screen and transfers it to paper or a hard copy. There are many different types of printers with various levels of quality. The three basic types of printer are; dot matrix, inkjet, and laser.

• Dot matrix printers work like a typewriter transferring ink from a ribbon to paper with a series or 'matrix' of tiny pins.
• Ink jet printers work like dot matrix printers but fires a stream of ink from a cartridge directly onto the paper.
• Laser printers use the same technology as a photocopier using heat to transfer toner onto paper.

Digital flash drives:-

work slightly differently as they use memory cards to store information so there are no moving parts. Digital cameras also use Flash memory cards to store information, in this case photographs. Hand held devices use digital drives and many also use memory cards.

PROTECT YOUR PC WITH A SURGE PROTECTOR:-

                                                                                     This is an area that is critical to the continued operation of your PC. Power surges and lightning strikes can sometimes get coupled onto your PC through the power or phone line. These surges can damage your PC.

Surge protected power strips have snubber circuits that filter out these potentially dangerous power line transients.

PROTECT YOUR PC WITH A SURGE PROTECTOR:-

                                                                                     This is an area that is critical to the continued operation of your PC. Power surges and lightning strikes can sometimes get coupled onto your PC through the power or phone line. These surges can damage your PC.

Surge protected power strips have snubber circuits that filter out these potentially dangerous power line transients.

Boot Quicker:-

                        After displaying "Starting Windows…" on your monitor screen, by default, Windows pauses 2 seconds to allow you time to push F8 if you want to go to the Boot Menu Screen. You can change it so it doesn't pause at this point. Simply open MSDOS.SYS and change the BootDelay line to BootDelay=0. The number you put in the BootDelay= line is the number of seconds Windows will pause. This means that you're going to have to be pretty fast at hitting F8 if you want to boot to the StartUp menu in Win95. In Windows 98, you just have to hold down the CTRL key as the computer boots.

Remove the Flying Windows Logo:-

If you don't want to see the Flying Windows Logo every time you start Windows, you can turn it off in MSDOS.SYS. In the [options] section, change the line Logo=1 to Logo=0.

Boot To DOS:-

                                   Sometimes you may want a computer to boot to a DOS prompt instead of into Windows, especially when trying to troubleshoot a boot problem. This can be done by making a simple change to the MSDOS.SYS file in the root directory of your hard drive. Remove the 'hidden' and 'read-only attributes on MSDOS.SYS. Open it in NotePad and change the line BootGUI=1, to read BootGUI=0. Change the attributes back. Now your computer will boot to the DOS Prompt. Maybe you want to do this from the DOS Prompt: Make sure you're in the root directory of your C drive. Type : attrib -h -r msdos.sys at the DOS Prompt, then press ENTER. Now type: edit msdos.sys and press ENTER again. In the Editor, change BootGUI=1, to read BootGUI=0. Save and exit. Change the file's attributes back (attrib +h +r msdos.sys), and reboot.

Removing the Attributes on MSDOS.SYS:-

                                                                                                    Warning: If DOS is your computer's Operating System, Do Not remove the attributes or change the contents of the MSDOS.SYS file.
Although MSDOS.SYS is a required start-up file in Windows 9x, it is no longer a binary file as it was in DOS. It's actually a simple text file that contains start-up information for the Operating System. It tells the computer where to find the Registry, and defines the location of the boot drive, different start-up files, and the location of the Windows directory. But, it also has an [Options] section that allows you to manipulate some of the start-up processes. Windows 9x sets the System, Hidden and Read-only attributes on MSDOS.SYS. Because it is a system file, it's important to back it up before you fool with it.