EB-2 or the Employment-Based second preference visa is granted in case the applicant holds an advanced or equivalent degree or a foreign national with exceptional ability and where the employers are willing to sponsor the applicant.
A Department of Labor (DOL) permanent labor certification enables a business to hire a foreign worker to work permanently in the United States. The DOL must certify to the USCIS that there are insufficient US workers capable, willing, qualified, and available to accept the job opportunity in the area of intended employment.
PERM process or Program for Electronic Review Management is when the employer has to prove the need to immigrate a foreign worker for the said job.