Answer:
According to Article II, Section 1 of the United States Constitution:
"No person except a natural born citizen, or a citizen of the United States, at the time of the adoption of this Constitution, shall be eligible to the office of President; neither shall any person be eligible to that office who shall not have attained to the age of thirty-five years, and been fourteen years a resident within the United States."
Our current president is Barrack Obama (2010). The president must win a fair election, and have an inauguration to be sworn into the position of presidency.