The US Legal System is a complex organization of Federal and State governmental divisions. In order to understand the US Legal System, you should first know which laws, rules or regulations control. In other words, which laws have priority or controlling effect.
The U.S. Constitution is the highest law of the land. Federal Laws enacted by the US Congress come next. This does not mean that the Federal Congress can adopt laws that control States in every situation. It can’t unless the law can be applied to the States under the US Constitution and Court decisions.
Each State has a legislature that adopts State Laws called “statutes”. Those statutes are sometimes complied into what is referred to ad a Code. This is nothing more than a codification of all the applicable statutes.