Dual Mode Fiber is a less common type of optical fiber that can support both single-mode and multimode transmission. Unlike Single Mode Fiber (SMF), which is designed for long-distance, high-speed communication with a small core size (typically 8-10 microns), and Multimode Fiber (MMF), which has a larger core (50-62.5 microns) for short-distance, high-bandwidth applications, Dual Mode Fiber combines aspects of both. This allows for flexible deployment in networks where both transmission types are needed. However, due to differences in core structure and light propagation, it is not widely used in standard optical networking.