Okay kiddo, so you know how when Mommy or Daddy asks you to clean your room, they come and check to make sure you did a good job? Well, when a big company makes a lot of money and has a lot of things going on, they hire someone called an auditor to check their financial statements and make sure everything looks good.
Now, auditors have some rules they have to follow when they do their job, and those rules are called Statements on Auditing Standards (or SASs for short). Think of them like a checklist for the auditor to make sure they're doing their job the right way.
These SASs help the auditor make sure the company's financial statements are accurate and give a good picture of how the company is doing. So just like how Mommy and Daddy want you to clean your room properly, companies want auditors to do their job properly to make sure everything is okay.
And that's basically what Statements on Auditing Standards are all about, making sure auditors do their job correctly and give an accurate report on the company's money.