Household electricity and its current flow can be easy to understand if you compare it to the plumbing in your home. If you think about it, electricity and water both enter your home and exit it after being distributed throughout home. Electricity flows through a network of boxes and devices to reach its destination.
Let's look at a comparison to plumbing. Water comes in the home through via a pressurized water supply from a well or city supply. It is then distributed to the faucets and then returns with no resistance through the drain system.
Likewise, electricity flow from the utility lines, through the service entrance pole, to the meter, disconnectand then the electrical panel. The panel then distribute the current through circuit breakers or fuses to the electrical devices that are supplying power to electrical loads like lighting, appliances, and other loads. This distribution takes place through switches, receptacles, often called outlets, and lighting fixtures.
Just like larger water pipes carry more more flow, so do larger wires carry more current. The amperage rating of wire determines the size of circuit breaker needed to protect the circuit from overloads.
When you hear the word pressurized, with water it means a greater force of water will flow from a spigot or garden hose when the pressure is higher. With electricity, the electrical pressure of electrical current is called voltage. It is the ratig that your electrical components run on. For example, an appliance may be rated for 120 volts, used for lighting or general receptacle power, or it may be rated for 240 volts, as is the case of an electric dryer or range.
Here it is in a nutshell. The electricity enters the home, is used by lighting, appliances, furnaces, wells, TVs, and everything that plugs into your home. Anything unused makes a return to the entry point via the neutral wire. This return is considered to not be under pressure, much like water going down the drains of your home.
Learn more with these electrical breakdown links!