If you've ever changed a battery or plugged something into a wall outlet, you've dealt with voltage. But what is voltage, really? In the simplest terms, voltage is the pressure from an electrical circuit's power source that pushes charged electrons (current) through a conducting loop.

Think of it like water in a pipe. The voltage is the water pressure. The higher the pressure, the more "push" the water has. This is a perfect analogy for understanding electrical potential difference, which is the more scientific term for voltage.

Volts vs. Amps vs. Ohms: The Holy Trinity of Electricity

It's impossible to understand voltage without its two best friends: amperage (current) and resistance (ohms).

• Voltage (Volts): The pressure that pushes the electricity.

• Amperage / Current (Amps): The flow rate of the electricity. (How much water is flowing through the pipe).

• Resistance (Ohms): The friction or opposition to the flow. (How narrow the pipe is).

The relationship between these three is the most important rule in all of electronics: Ohm's Law.

Ohm's Law Explained

Ohm's Law is a simple formula that connects voltage, current, and resistance.

The Formula:
Voltage (V) = Current (I) × Resistance (R)

This means:

• If you increase the pressure (Voltage), the flow rate (Current) will also increase.

• If you increase the friction (Resistance), the flow rate (Current) will decrease.

This simple V = IR formula is the foundation for millions of electronic circuits.

Internal Link: To see this formula in action, check out our Ohm's Law Calculator.

Where Do We Find Voltage?

• Batteries: A standard AA battery has 1.5 volts. A car battery has 12 volts.

• Wall Outlets: In the US, a standard outlet provides 120 volts. In Europe, it's typically 230 volts.

• USB Ports: A standard USB port provides 5 volts.

Internal Link: Wondering how to measure this pressure yourself? Read our simple guide on How to Use a Multimeter to Measure Voltage.