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Modem
It stands for Modulator-Demodulator. A modem is a
peripheral device which modulates (converts analog
signals to digital signals) from the transmitting workstation
and demodulates (converts digital signals into analog 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 to browse 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. 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: It was used to connect the keyboard and mouse with the
computer. Now, 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

