"Special Topics of Engineering," "Individual Studies," and "Special Projects for Engineering" are non-mandatory courses offered by engineering departments that serve as flexible options for students. These courses typically do not follow a standard curriculum and are designed to allow students to earn credit for work outside of regular classes. The specifics of these courses can vary by university. For instance, a "Special Topics" course may cover unique subjects not listed in the official catalog and can be taught like a regular class, but only for a limited time before needing to be proposed as a standard course. In contrast, a "Directed Study" is student-initiated, focusing on a self-chosen topic under the supervision of a professor, with minimal direct instruction. Overall, these courses provide a way for students to explore individual interests and gain credit for their efforts outside the traditional curriculum framework.