Rajnikant Bal presented a technical seminar report on flash memory. Flash memory is a type of non-volatile solid state memory that can be electrically erased and reprogrammed. It provides benefits over traditional hard drives by being compact, lightweight, and energy efficient. Flash memory is widely used in devices such as digital cameras, smartphones, and MP3 players due to these advantages. The seminar covered the basic workings of flash memory cells, how erase and write operations are performed, and various applications of flash memory technology.