who appoints the governor of a state and why?

Governor of the State is appointed by the presidentHe should be an Indian citizen, above 35 years of age, should not be a member of either Rajyasabha or Loksabha nor the Legislative assembly of the state, also he should possess the eligibility qualifications of an MLA, he shouldn't be the owner of any office of profitHe is the nominal executive and CM is the real executive. This means that even though it is the CM who works behind various laws, no bills are passed unless it is signed by governor. Governor is the representative of the State. When there is conflict between a central interest and the state interest, the opinion of governor matters.Governor holds the office for 5 years.