MOU - Memorandum Of Understanding
Memorandum Of Understanding is a legal document that expresses mutual agreement on an issue between two or more parties. It is often the first stage in the formation of a formal contract that includes each parties requirements and responsibilities. MOUs are very common and are used for domestic purposes like agreement between different companies or institutions.
If some educational institute named "ABC" want their student to be trained by some company named "XYZ". Then, "XYZ" may ask the institute to sign the "Memorandum Of Understanding", after which, their students would not be able to contact any other company for that specific training.