Type II superconductors are materials that can conduct electricity without resistance below a certain temperature, known as the critical temperature. Unlike Type I superconductors, which completely expel magnetic fields, Type II superconductors allow magnetic fields to partially penetrate them in specific regions called vortices. This unique behavior enables them to maintain superconductivity in higher magnetic fields. These superconductors are often made from complex compounds, such as niobium-titanium or high-temperature superconductors like YBCO (yttrium barium copper oxide). Their ability to operate in strong magnetic fields makes them useful in various applications, including MRI machines and particle accelerators.