Windows 8.1 x64, an iteration between the controversial Windows 8 and the widely embraced Windows 10, retains the tile-based interface while addressing many of its predecessor's criticisms. Offering enhanced performance and stability on 64-bit systems, it brings refinements like the return of the Start button and improved multitasking capabilities. With better compatibility for modern hardware and software, it caters to a broad user base. Security features like Windows Defender bolster protection against malware. Despite these improvements, its adoption was overshadowed by the more popular Windows 7 and later Windows 10. Nonetheless, it remains a viable choice for users seeking a balance between familiarity and modern features.