what is the first name of  the instructor who teaches the least number of courses?
SELECT T2.Fname FROM COURSE AS T1 JOIN FACULTY AS T2 ON T1.Instructor  =  T2.FacID GROUP BY T1.Instructor 
ORDER BY count ( * )  LIMIT 1
first name of the instructor = Fname; least number of courses taught by an instructor refers to MIN(COUNT(course));