Wikipedia about electric current
The movement of electric charge is known as an electric current, the intensity of which is usually measured in amperes. Current can consist of any moving charged particles; most commonly these are electrons, but any charge in motion constitutes a current.
By historical convention, a positive current is defined as having the same direction of flow as any positive charge it contains, or to flow from the most positive part of a circuit to the most negative part. Current defined in this manner is called conventional current. The motion of negatively charged electrons around an electric circuit, one of the most familiar forms of current, is thus deemed positive in the opposite direction to that of the electrons. However, depending on the conditions, an electric current can consist of a flow of charged particles in either direction, or even in both directions at once. The positive-to-negative convention is widely used to simplify this situation.
What does the electrician?
Most people more or less have some idea of ??what is in their work electrician. Increasingly, however, his task is not only the installation and repair of electrical installations as well as for solving a variety of problems with the existing installations. It is true that, in a residential electrician main task is to install appropriate cables still in the process of building a house. Electricians installations also involved in other, less associated with electrical devices such as intercoms or monitoring. Often, as far as their powers, electrician designs the future electrical installations.
Protection of electrical networks
Actually, modern technological solutions in the design and construction of electrical installations, make electrical services are becoming less necessary. Excellent insulation of cables and their arrangement can make the most electrical work will be the installation of such electrical lines, not during their operation. Does this mean that in the future, avoid any electrical failures? The answer to this question is simple and of course negative, because although more and better solutions are continuously implemented many failures simply impossible to predict, even using the most modern electrical installations.