Wave soldering

Wave soldering is a way to put tiny pieces onto a board, like a puzzle. First, people put tiny parts onto the board. Then, the board goes through some special machines. These machines heat up a special metal called solder until it turns into a liquid. This liquid metal has waves on it, like at the beach.

The board goes over the liquid metal, and the waves wash over the board. The waves pick up pieces of the liquid metal and stick them onto tiny parts, like the little arms of a puzzle piece going into a slot. Then, the board cools down and the liquid metal turns back into solid metal, like when water from the beach dries up.

Once the board is cooled down, all the tiny pieces are stuck tight, like puzzle pieces glued together. This is how wave soldering works.