OPT refers to Optional Practical Training. It is a program that allows international students in the USA to gain temporary employment for a period of no more than 12 months, OPT can be undertaken and completed before or after one completes their academic program. REMEMBER that international students are only permitted to work for a total period of 12 months under this program including period before and/or completion of their academic degrees. 

International students completing degrees in science, technology, engineering, and mathematics (STEM) are allowed to apply for a 24 months extension on the completion of their OPT.

CPT refers to Curricular Practical Training. This is a program that permits international students in the USA to temporarily gain work experience related directly to their majors. This can be in the form of employment, paid or unpaid internships or through co-operative education.