Electronics basics · Lesson
7 min read
Breadboards and wiring
How the holes inside a breadboard are connected, and habits that prevent mistakes.
What You Will Learn
- Know which breadboard holes are connected
- Use power rails correctly
- Follow wire colour conventions
A solderless breadboard has metal strips under the holes. Each short row of 5 holes (a–e, and f–j) is connected. The long rails along the edges are connected along their length and are used for power (+) and GND (−).
- Components that bridge the centre gap (like buttons and chips) are not shorted.
- Red wires for +, black or blue for GND — it makes mistakes easy to spot.
- On long breadboards the rails can be split in the middle; check for a gap in the printed line.
The Circuit Lab connects parts with wires directly; a breadboard view is planned. Every wire you draw is the same as a breadboard row that joins two holes.
Unplug USB before rewiring a real circuit. A stray wire between 5V and GND can reset or damage the board.
Check Your Understanding
Test what you learned in this lesson