Which file system utilizes magic numbers to identify files to the operating system?

The Ext3 file system utilizes magic numbers to identify files to the operating system, particularly for recognizing file types and structures. Magic numbers are specific byte sequences located at the beginnings of files that serve as identifiers for the file format, enabling the operating system to determine how to properly handle the file. In the case of Ext3, which is an evolution of the Ext2 file system used primarily in Linux environments, it employs these magic numbers to ensure that the files are correctly interpreted and managed.

On the other hand, while NTFS, FAT32, and FAT16 are other common file systems, they do not primarily rely on magic numbers for file identification in the same way Ext3 does. For example, NTFS employs a more complex structure with metadata and attributes to manage files, while FAT32 and FAT16 use File Allocation Tables to organize files without relying heavily on magic numbers. Therefore, Ext3 stands out for its specific use of magic numbers in this context.