A deputy prime minister or vice prime minister is, in some counties, a government minister

Minister (government)

A minister is a politician who holds significant public office in a national or regional government. Senior ministers are members of the cabinet....

 who can take the position of acting prime minister

Prime minister

A prime minister is the most senior minister of cabinet in the executive branch of government in a parliamentary system. In many systems, the prime minister selects and may dismiss other members of the cabinet, and allocates posts to members within the government. In most systems, the prime...

 when the prime minister is temporarily absent. The position is often likened to that of a vice president

Vice president

A vice president is an officer in government or business who is below a president in rank. The name comes from the Latin vice meaning 'in place of'. In some countries, the vice president is called the deputy president...

, but is significantly different, though both positions are "number two" offices. The position of deputy prime minister should not be confused with the Canadian

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 office of the Deputy Minister

Deputy Minister (Canada)

In Canada, a deputy minister is the senior civil servant in a government department. He or she takes political direction from an elected minister. Responsibility for the department's day-to-day operations, budget and program development lie with the deputy minister...

 of the Prime Minister of Canada

Prime Minister of Canada

The Prime Minister of Canada is the primary minister of the Crown, chairman of the Cabinet, and thus head of government for Canada, charged with advising the Canadian monarch or viceroy on the exercise of the executive powers vested in them by the constitution...

, which is a non-political civil servant position (Nor does the Deputy Prime Minister of Canada act as a "number two").