Page 11 - TP_iPlus_V2.1_Class7
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Modem

                 It  stands for  Modulator-Demodulator.  A  modem is a
                 peripheral device which modulates (converts digital signals
                 to analog signals) from the transmitting workstation and
                 demodulates (converts  analog  signals to  digital signals) at  the  recipient’s workstation.  The
                 sending and receiving ends of the communication must  have a modem. Nowadays,  mobile
                 phones have inbuilt modem devices that help users browse the internet. Modems are of two
                 types: internal and external. An internal modem is located inside the CPU box, just like the
                 motherboard plate. On the other hand, an external modem is a separate device that you can
                 connect to the computer with the help of a USB port. It generally contains indicators in the form
                 of small lights.
                 Ports


                 Computer  ports  are  an  interface  between  the  computer  and  peripheral  devices like mouse,
                 keyboard, monitor, printer, speaker, flash drive, pen drive, etc. A computer port acts as a point of
                 connection where the cable or plug from the peripheral device can be plugged to facilitate data
                 flow from and to the device.
                 A computer port is also called a communication port as it facilitates communication between the
                 computer and its peripheral device. Based on the type or protocol used for communication,
                 ports can be categorized as Serial Ports and Parallel Ports.

                 •  Serial Port: It is an interface  through which peripherals  can be
                   connected using a serial protocol which involves the transmission of
                   one bit of data at a time over a single communication line. It is also
                   called a communication port.  Generally,  serial ports are used to
                   connect the modems.
                                   •   Universal Serial  Bus  (USB)  Port: It is also known  as a standard  cable
                                      connection  interface,  and is to connect  USB  devices and provide  power
                                      supply to the devices connected to it. Mouse, keyboard, etc., are connected
                                      to the computer with the help of USB ports.

                 •  Parallel Port: It is an interface through which the communication between a computer and
                   its peripheral device takes place in a parallel manner i.e., data
                   is transferred in or out parallely or simultaneously using more
                   than one communication line or wire. Printer port is an example
                   of parallel port.
                              •  PS/2 Port: PS/2 ports were once a common way to connect the keyboard and
                                 mouse with the computer. Nowadays, USB ports are used in place of PS/2 ports.


                 •  Video Graphics Array (VGA) Port:  It is found in computers, projectors, video
                   cards and many TVs. The connector is called DE-15. It is also similar to the
                   serial port. The only difference is that it has holes instead of pins.  It is a D
                   shaped sub connector consisting of 15 pins in 3 rows. With the advancement
                   in technology, HDMI and Display ports are used in place of VGA ports.


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                                                                              Computer—Hardware Components
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