Current is flow of electrons???

During initial studies we studied that current is flow of electrons in an circuit and current will always flow from high potential to low potential. Due to flow of electrons we will feel current.

But in electrical circuits it is the vibration of electrons in a circuit not flow of electrons. As you know that in metals there are free electrons revolving around the orbit and of these electrons are released from metal orbit than there will be reduced electrons in metal orbit which will results into non conductive metal which is conductive due to these free  electrons and if these electrons are dislodged and get consumed than ultimately metal will loose its conductivity as these free electrons will get consumed at negative terminal.

In actual its vibration of electrons not flow of electrons in that condition when high potential is applied to metals than due to this high potential kinetic energy of electrons get increased and these electrons starts vibrating at there place and these vibrating electrons release the energy to come at zero potential and during this they release energy which is principle behind electricity in conductors.

Now electrical conductivity of metals depends upon following factors:-

(i) More the free electrons available more conductor is the particular metal. 

(ii) Drift velocity through metal on applied electrical field.

Aluminum is most widely used conductor in electrical systems considering lower cost than copper. 

In Indian books we read about flow of electrons. 

There is more general concept which will clear more about vibration of electrons in power plants, power is generated by rotation of alternator in that alternator electrons are not generated it is only vibration of electrons which is generated with magnetic field. If there is flow of electrons than from where these electrons are generated and if these are electrons generated inside metals from free electrons in their orbit and soon their orbit will get emptied and metals will lose their conductivity over the period of time.