What does it mean when the president declares a national emergency

A country's government or president can declare that it is in a state of emergency. This means that the government can suspend and/or change some of the functions of the executive, the legislature or the judiciary while the country is in this exceptional state, while alerting its citizens to adjust their behavior according to the new situation, in addition to command government agencies to implement emergency plans. This way, a government can declare a state of emergency in response to natural or man-made disasters, periods of civil unrest, declarations of war or situations involving internal or international armed conflicts.