A SNP is a variation of a single nucleotide between individuals. These polymorphisms can therefore be used to discern small differences both within a population and among different populations.
President of the United States. The President of the United States is the head of state of the U.S., the chief executive of the federal government, and Commander-in-Chief of the armed forces. The United States was the first nation to create the office of President as the head of state in a modern republic.
For a list, see List of Presidents of the United States. The President of the United States (informally referred to as POTUS) is the head of state and head of government of the United States. The president directs the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces. The president is considered to be one of the world's most powerful political figures, as the leader of the only contemporary global superpower.