Alright kiddo, let's talk about something called decidability. This is a big word that basically means whether or not we can figure out the answer to something using rules and logic.
Imagine you have a big puzzle to solve, like a maze. You know the starting point and the ending point, but you need to figure out how to get there. Decidability is like asking, "can we figure out how to solve this maze using the rules and logic we have?"
Sometimes, the answer is yes! We can use logic and rules to solve the puzzle or problem. Other times, the answer is no. It might be too complicated or there might not be enough information.
There are some problems and puzzles that we know are always going to be solvable using rules and logic, like algebra equations or Sudoku puzzles. We call these problems "decidable".
But there are also some problems that we know we can never solve using rules and logic alone. These problems are called "undecidable". They might be too complex, like trying to find every possible combination of letters in the alphabet. Or they might not have a clear solution, like trying to figure out if there is extraterrestrial life in the universe.
So, in short, decidability is about figuring out whether or not we can use logic and rules to solve a problem or puzzle. Sometimes we can, and sometimes we can't.