Imagine you have a bunch of numbers in a big box. You want to sort them out and make them easier to work with. So, you divide them into two new boxes - one has some important information, and the other has some extra information you don't really need right now.
This is kind of what we do with LU reduction. It is a way to simplify a big group of numbers or equations, so we can solve them more easily. Instead of working with all the numbers at once, we split them into two smaller groups - one with the important stuff, and one with the extra details we don't need right now.
The LU stands for "lower-upper" decomposition, which is just a fancy way of saying we're breaking the big numbers down into two smaller groups. The lower part has some of the extra details we don't need right now, and the upper part has the important stuff we need to solve our problem.
Once we've separated the numbers into two smaller groups, solving the problem becomes a lot easier. We can work with the important information in the upper part of the box, and ignore the extra details in the lower part. This saves us time and energy.
So, in short, LU reduction is just a way to simplify a big group of numbers or equations, by dividing them into two smaller groups. This makes it easier to solve complex problems, and saves us time and energy in the process.