Electricity is a basic part of nature and it is one of our most widely used forms of energy.
Electricity is about charge . Charge is a property of electrons and protons which are part of an atom . Electrons have negative charge and are mobile because they have 1/1830 of the mass of the positive proton.
Neutrons have the same mass as a proton , but no any charge.
Electron in motion is called electric current which we use every day in our homes . In other words, Electricity is simply a flow of negative charged particles, called electrons through conductors like copper wire.
In most metals, the nuclei of atoms (protons & neutrons) are bonded together.
The pressure the electrons in the wire is called voltage and is measured in units called volts (V) .
The amount of electrons moving past a certain point on a wire is called the current, which is measured in units called amperes (Amps or A).
Power Supply In a personal computer (PC), the power supply is the metal box usually found in a corner of the case. The power supply is visible from the back of many systems because it contains the power-cord receptacle and the cooling fan
Modern motherboard uses a 20 or 24 pin P1 power connector . Some motherboards may require special 4-, 6- or 8-pin connectors to supply extra power . The ATX, NLX and SFX power supplies have 20-pin connectors that attach to the motherboard.
Power Supply Connections to Peripheral Hardware - MOLEX
the most commonly used
provides both 12 volt and 5 volt
hard disk drives, CD Rom drives
Power Supply Connectors to Peripheral Hardware - Mini Connectors