If you are interested in learning everything about electricity, you should start by understanding the basic components that make up any electrical design and how they work. Think about how the great pyramids of Egypt were built using just blocks of rock. The rocks themselves were nothing, but when combined with a careful design they formed such grand structures!

electrical components

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Similarly, you need to know about the basic electrical components and how they work together to create wonderful modern electrical systems. Below you will find information about the most common electrical components:


The very first component that you should know about is the resistor. It is fairly easy to assume that a resistor, as the name suggests, will resist electricity that flows through it, and you would be correct in that assumption too! Any situation that demands the flow of current to be controlled at a desired level will require a resistor.


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Here are two scenarios that better explain what a resistor does. In both cases, we will be turning on a LED:

Scenario 1 – Without Resistor

  • You have power supply on one side.
  • You connect the LED on the other end.
  • The full force of the electricity hits the bulb.
  • This overloads the LED, eventually burning it out completely.

Scenario 2 – With Resistor

  • You have power supply on one side.
  • You connect this to a resistor.
  • The resistor in turn connects to the LED bulb.
  • Electricity flows through the resistor and into the bulb.
  • You can control the amount of electricity that needs to flow to the bulb. As a result, the LED won’t be overloaded and it won’t burn out.


If a resistor is like a cushion that is used to control the flow of electricity, then capacitors are like small rechargeable batteries that store small amounts of charge in them. Capacitors do two things at the same time:

  • They allow AC, or Alternating Current, to flow through them.
  • They resist the flow of DC, or Direct Current, through them.
collection of capacitors

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By so doing, they are able to stabilize almost any circuit. There are two types of capacitors that are primarily used:

  • Polarized capacitors – these have a positive and negative terminal
  • Non-polarized capacitors – these do not have any positive or negative terminals

Light Emitting Diode (LED)

I briefly alluded to LEDs in the scenarios that were used under “Resistors” above. LEDs are just like bulbs except that they are extremely reliable. You can find them on practically every appliance in your home that features some kind of an indicator light. A typical LED bulb can last decades with no sign of dying.


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Since they are so reliable, they are used to indicate the state of current at any point in a circuit. An important task like checking the output voltage or current on a circuit becomes simpler with these light-based indicators.


The resistors, capacitors, and LEDs are the simple stuff in electrical circuits. Now, let us talk about the first complicated component – the transistor. Transistors are used to build complex electrical systems, such as amplifiers for instance. A simple way to understand transistors is to think of a switch. A basic switch has an “on” and an “off” state. These are controlled by the position of the switch, which is changed manually.

various transistors

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A transistor is a more advanced switch that has multiple output states. Unlike a switch, you cannot change these states manually. The only way to switch the transistor between various states is to run current through it. By controlling the current that flows through the transistor, you can control the output state to achieve the results you desire.


Inductors are just as complicated as transistors. Just like transistors, inductors are used to build complicated electrical systems. Unlike transistors though, inductors are essentially coils of wire that are wound around other components. They are used as filters.


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Of all the electrical components mentioned on this page, you will most likely not use inductors for basic circuit designs. Nonetheless, depending on the particular project that you are working on, inductors just might make an appearance in the circuit’s design.

Integrated Circuit (IC)

Integrated circuits are electrical components that combine, or integrate, numerous electrical components, including the ones that were previously mentioned. One IC can act like a transistor while another IC can act like a resistor.

integrated circuit

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An IC is like a ready-made chip that you can use to complete the project you want to build without having to use lots of single transistors or capacitors. As you upgrade from using basic components to integrated circuits, you will find that it is almost always easier to use ICs for your entire project than using individual components.

In this post, I gave you a small introduction to the basic electrical components that you need to know about before you start working with electrical systems. The simplest plan would be to start with capacitors and resistors, moving up to using ICs, and eventually building your own systems for complex or advanced projects. When you are ready, pick up a starter kit and go crazy with it!