OPT gives F-1 students a chance to work in the U.S. for as long as a year after they graduate, as long as the job is in their field of study. Graduates in STEM fields might be able to get a two-year extension, for a total of three years. Students need to apply to USCIS through their school's DSO and get an EAD to participate. OPT is a good way to get practical experience and could open the door to an H-1B work visa if a company sponsors the student.