# Six Electrical Terms That You Need to Know Whether you’re a seasoned electrical expert or just getting started, you should know some important electrical terms. These six will help you make sense of everything from the breaker box to the main switch on your light fixture.

The path that electrons travel to move from one point to another. A circuit is complete or closed if no gaps stop the flow of electrons.

1. ## Current

Current is a measure of the flow of electric charge from one point to another in an electrical circuit. It is often measured in amperes, abbreviated as “amps.”

The amount of current that flows through a circuit is determined by how many charges pass through a cross-section of wire in a second. This is why some circuits have more current than others. In electricity, there are two main types of current. These are conventional current and electron flow.

1. ## Voltage

Voltage is one of the most important and widely used electrical units essential in all electrical and electronics engineering aspects. It is a derived unit in the International System of Units named after the Italian physicist Alessandro Volta who invented the first electric battery.

Voltage is a pressure or potential difference that makes possible the flow of electricity in a conducting path such as a conductor or closed electric circuit. It can be a source of alternating current (AC) or direct current (DC).

1. ## Resistance

Resistance is a measure of the opposition to current flow within an electrical circuit. It is measured in units called ohms, symbolized by the Greek letter omega (O).

Resistive materials obstruct the movement of an electric current, just like water offers friction when it flows through a pipe. This resistance causes some of the energy used to push a current through to be dissipated and is usually undesirable.

The unit of resistance is the Ohm, named after the German physicist Georg Ohm. He formulated the relationship between voltage, current, and resistance, called Ohm’s law.

1. ## Power

Power measures how much energy is used in a machine or person. It is usually expressed in watts. When working in electrical engineering, it is essential to understand the terminology around power as it is a very important part of the job.

One of the terms you will be taught is ‘power’; this is an important term as it is a key part of any circuit and can indicate how much heat is dissipated in a unit or component.

1. ## Efficiency

Efficiency is the ability of a system to deliver power at the maximum possible output for its size, power factor, and cost. It is usually used to describe a system’s overall performance but can also be applied to specific equipment, such as the energy consumption of an air conditioning unit.

One electrical energy efficiency measure type is watt-hours per hour (watt-hours). This measure indicates the amount of work a circuit does at a steady rate. It is calculated by multiplying the current flow (in amperes) by the volts of electrical pressure driving it.

1. ## Energy

Electricity is a form of energy that comes from a flow of electrical charge. This can be potential or kinetic energy but is usually encountered as potential energy.

In other words, electricity is generated when a moving charged particle, such as an electron, or a changing magnetic field induces an electric current in a conductor.

Electricity is used to power many devices we use every day, including lights, appliances, and our transportation systems. Biology also uses it to fuel and regulate the body’s natural functions, such as producing enzymes or building muscle.