The movement of electric charge is known as an electric current, the intensity of which is usually measured in amperes.
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.Źródło: https://en.wikipedia.org/wiki/Electricity
Often, as far as their powers, electrician designs the future electrical installations.
An electrician's license entitles the holder to carry out all types of electrical installation work in Australia without supervision. However, to contract, or offer to contract, to carry out electrical installation work, a licensed electrician must also be registered as an electrical contractor. Under Australian law, electrical work that involves fixed wiring is strictly regulated and must almost always be performed by a licensed electrician or electrical contractor. A local electrician can handle a range of work including air conditioning, data, and structured cabling systems, home automation & theatre, LAN, WAN and VPN data solutions, light fittings and installation, phone points, power points, safety inspections and reports, safety switches, smoke alarm installation, inspection and certification and testing and tagging of electrical appliances. Electrical licensing in Australia is regulated by the individual states..
In Western Australia the Department of Commerce tracks licensee's and allows the public to search for individually named/licensed Electricians.Źródło: https://en.wikipedia.org/wiki/Electrician