Think of a partition as a container for data, like one drawer of a file cabinet. Each partition uses a file system to store and name data. Windows 98 and Me use the FAT32 file system. FAT32 allows for greater maximum partition sizes and stores data more efficiently than the FAT16 file system used by DOS and the first versions of Windows 95.
Windows NT introduced the NTFS file system, which uses space more efficiently and offers better data security. Windows 95, 98, and Me can't "see" the data in an NTFS partition; however, Windows 2000 and XP can read from and write to both NTFS and FAT32 partitions.