The Donald Trump administration finalized the 4-year fixed stay rule for international students which means students coming to the US will be allowed to stay only for four years -- the duration of most of the courses, and if they need to stay longer, if they start doing their OPT etc, they will have to seek an extension from the Department of Homeland Security before their authorized stay expires. The existing rule does not have a fixed duration, and students are allowed to remain in the US as long as they comply with all visa requirements.