So, when you have your piggy bank and you put some coins in it, you want to know how much money you have right? In the same way, big companies also have to keep track of how much money they have and how much they spend.
In France, they have a special set of rules called "French Generally Accepted Accounting Principles". These rules tell the companies how they should write down all the money they have and all the money they spend.
It's like having a really big notebook where you write all the things you buy and all the money you get. But it's very important to write everything down in the right way, so that when you look at it later, you can understand exactly what happened with the money.
So, these rules help the big companies in France keep track of all their money and make sure they are doing things the right way. It's like having a set of instructions that everyone follows so that it's easier to understand what's going on with the money.