"REU" stands for Research Experiences for Undergraduates and is a popular program for undergraduate students in the United States to participate in research activities under the guidance of experienced faculty researchers. Synonyms for this term include "undergraduate research opportunities" (URO), "research internships for undergraduates" (RIU), and "undergraduate research programs" (URP). These programs provide students with hands-on experience to enhance their academic and career goals. They also allow students to work on cutting-edge research in a variety of fields while building relationships with their mentors and peers. Additionally, these programs often provide funding opportunities and can boost students' resumes and applications for graduate school and employment.