How a Breadboard Works: Clips, Rows, Power Rails and Chips

Have you ever wondered what's actually inside of a breadboard?

Every circuit you build on it holds together without a single drop of solder, and this is why.

Under every hole sits a little metal strip.

It is made of phosphor bronze, a springy kind of copper folded into a row of tiny clips.

When you push a leg in, the two jaws of the clip spread apart and squeeze back on it.

That squeeze is the connection. But why do the holes come in short rows of five?

Because one strip runs under all five, so anything you push into those five holes is joined together as if you had soldered it.

So what is the channel in the middle for?

It cuts every row in two. The gap is exactly as wide as the gap between the two leg rows of a chip.

So a chip straddles it, and every leg lands on its own strip with nothing shorting across.

And the long lines along the edges? Those are the power rails.

Under each one is a single strip that runs along the board.

So plus and minus are right next to every row.

Your ESP32 sits over that same channel, one row of pins on each side, so every pin gets its own strip