The document discusses three key computer components: the motherboard, microprocessor, and USB. The motherboard is the main circuit board that connects other internal devices like the CPU, memory, and video card. The microprocessor, often referred to as the CPU, performs all the computations and is the "brain" of the computer. USB (Universal Serial Bus) allows multiple devices to connect to a single port and provides both data transfer and power delivery through its cable.

1. Motherboard, Microprocessor
and USB
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2. Motherboard
• Motherboard is the main core of the computer.
• It is also known as Printed Circuit Board (PCB) or circuit board or
System Board.
• It is the main circuit board in which many internal devices such as
video card, sound card, memory, CPU and other devices are
attached.
• None of the other card or devices can work without motherboard.
• Motherboard is a rectangular fiber glass with a printed circuit board
on the surface of which connects one component to another.
• Although the system board's physical structure has changed over
time, its logical structure has remained relatively constant.
• The system board of the personal computer consists of a
microprocessor, supporting circuits, ROM, the system's Primary
Memory units, keyboard interface, timing circuit etc.
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3. Motherboard
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4. Microprocessor
• Microprocessor is the brain of computer, which does all
the work.
• It is a computer processor that incorporates all the
functions of CPU (Central Processing Unit) on a single
IC (Integrated Circuit) or at the most a few ICs.
• Microprocessors were first introduced in early 1970s.
4004 was the first general purpose microprocessor
used by Intel in building personal computers.
• Arrival of low cost general purpose microprocessors
has been instrumental in development of modern
society the way it has.
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5. Microprocessor
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6. Universal Serial Bus
• It is a high speed serial bus.
• Its data transfer rate is higher than that of a serial port. It
allows interfacing several devices to a single port in a daisy
chain.
• It provides power line along with data lines.
• USB cable contains 4 wires two out of four wires in the USB
cable are used to supply electrical power to devices and
two are reserved for send data and commands.
• It can operate in two modes i.e. Low speed mode and
medium speed mode.
• In low speed mode data transfer rate is 1.5 Mbps and at
medium speed mode data transfer mode is 12 Mbps.
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7. USB
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