The Marriott Employee Offer is a discounted rate that allows Marriott employees to stay at Marriott hotels at a discounted rate. On the intranet site, look for the "Employee Benefits" or "Employee Only Benefits" tabs, and you'll see all the benefits available to employees.
It's important to note that Marriott's internal employee discounts are limited to booking a stay for yourself and your family, and cannot be transferred or used in conjunction with other discounts. In addition, depending on the hotel's policy it may be required to provide employee certificates and other relevant documents at check-in, so it is best to confirm the relevant regulations before booking to avoid affecting travel arrangements.