The first title in each category is a code. A code contains all laws currently in effect arranged by broad subject categories. Any amendments are incorporated. The second title in each category is a compilation of laws by year.
To find all current laws on a subject use a code. Look up your subject in the index volume(s) of the code. Go to the title number and section indicated. ALWAYS CHECK POCKET SUPPLEMENTS. To find U.S. laws by name use the "Popular Name Table" in the last volume of the USCA index.