A breadboard lets you build and change circuits without soldering. You push the legs of parts into the holes, and metal strips inside connect them.
How the holes are connected
- Terminal strips (the middle): each short row of 5 holes is connected. The gap down the centre splits the board in two halves.
- Power rails (the long lines on the sides): marked red (+) and blue (−). Each line is connected along its whole length.
Your first circuit: one LED
- Connect the battery's + to the red rail and − to the blue rail.
- Put a 390 Ω resistor from the red rail into a row.
- Put the LED's long leg (+) in the same row, and its short leg in the next row.
- Use a wire from that second row to the blue rail.
The LED should light. If not, turn the LED around — it only works one way.
Common mistakes
- Putting both legs of a part in the same row (it gets shorted).
- Forgetting that some long breadboards split the power rails in the middle.
- Pushing thick wires in too hard, which loosens the clips.
Next, try Ohm's law to choose resistors yourself.