Electronics is the study of the flow of electrons through materials and devices. Devices could be semiconductors, resistors, inductors, capacitors and vacuum tubes. An electronic component is any physical entity in an electronic system which affects the electrons. Current flows from +ve to -ve.
First of all you must be aware of what is an atom. Atom contains a nucleus to which electrons are tightly bound or loosely bound. Example wood, glass have tightly bound electrons has it is difficult for current to flow in them since there is less movement of electrons. Whereas Copper, iron, god, silver are having loosely bounded electrons to nucleus therefore current flow is more due to presence of free electrons. Generators use a magnet to move electrons. In an electrical circuit, the number of electrons that are moving is called the current, and it is measured in amperes. The “force” pushing the electrons along is called the voltage and is measured in volts. For example a battery is of 9v means it will push electrons with force of 9v.In US power outlets gives 120v whereas in India it gives 220v.
Increase in voltage increases current. Decrease in resistance will increase current flow.The advantage that alternating current provides for the power outlet is the fact that it is relatively easy to change the voltage of the power, using a device called a transformer.V=IR
Volts * Amps = Watts::Volts-Potential difference
If you allow electrons to move through a wire, they will create a magnetic field around the wire.Similarly, if you move a magnet near a wire, the magnetic field will cause electrons in the wire to move.
General Electronics is necessary for all of us to know. Being completely unaware of electronics basics terms will not help you at all. Having even little knowledge of electronics can also save you a lot of time and money. If you know basics of electronics you can yourself correct faults encountered in your electronics equipments. For e.g. say a telephone has got its wire broken and wire has got unsoldered, if you have a general idea of how to correct it you can do it by yourself by soldering it instead of submitting it at any shop. This was just an example. We must know how electrical circuits work and general electronic symbols and formulas.