Cold solder joint

Okay kiddo, so sometimes grown-ups need to use something called solder to connect parts together. It's like a glue made out of metal that melts with heat so it can stick things together.

But sometimes, if the grown-ups aren't careful, they might not heat up the solder enough or they might move the parts while they're cooling down. When that happens, it can create a "cold solder joint," which means the glue doesn't stick properly and the parts might come apart or not work right.

It's like when you're making a sandcastle at the beach and you're trying to stack the sand too quickly without making sure all the sand is wet enough to stick together. If you don't do it right, the sandcastle might fall apart.

So, for the grown-ups, it's important to make sure they melt the solder enough and don't move the parts after they put them together. That way, everything stays connected and works as it should.