H-1B visa is reserved for "specialty occupations." Those that require a at least a bachelor's degree in a specific subject or closely related subjects.
On April 1, 2015, U.S. Citizenship and Immigration Services (USCIS) will begin accepting H-1B petitions subject to the fiscal year (FY) 2016 cap. U.S. businesses use the H-1B program to employ foreign workers in occupations that require highly specialized knowledge in fields such as science, engineering and computer programming.
The congressionally mandated cap on H-1B visas for FY 2016 is 65,000. The first 20,000 H-1B petitions filed for individuals with a U.S. master’s degree or higher are exempt from the 65,000 cap.
This policy memorandum (PM) provides guidance on the adjudication of H-1B petitions for nursing positions. Specifically, this PM assists U.S. Citizenship and Immigration Services (USCIS) officers in determining whether or not a nursing position meets the definition of a specialty occupation. This PM supersedes any prior guidance on the subject.
Please check the attached document to read USCIS Policy memo.

I have finished my first review of H-4 EAD Regulations (effective 26 May 2015). Here are the takeaway points: