Thousands if not more. It hard to have exact number as there are Federal, State, County(Borough/Parish), and City/Town laws. Many of these laws overlap between the jurisdictions. Also on the more local level laws are created and removed on sometimes weekly basis.
The question is far too broad. There are many, many thousands of laws the US citizens have to abide by.
Stalking is illegal in all 50 states in the US.
too many
State laws vary across the country and laws are different in many countries. Please see: related links for U.S. Laws
About 300 new laws per year are passed in the US at least as far back as the 1970's.
laws
Roman law is important to us today becasue our society uses many of the roman laws of ancient Rome
Justinian's codes.
Because without these laws physics wouldn't make any sense and many of us would be confused.
All US states have laws that relate to littering, disposing of waste material, etc.
This types of US laws were considered to be civil laws.
The United States is a republic. We elect people to make our laws. There are too many of us for us all to go to Washington to make laws.