Ext2, Ext3, Ext4 are default file systems for most of Linux operating systems. They are all based on the UFS (UNIX File System). Ext3 and Ext4 introduced file system journaling.
FAT (File Allocation Table) file system is the primary file system in various operation systems: Microsoft DOS, Microsoft Windows 9x, UEFI, e.t.c. and is supported from the box by almost all available OSes.
Systems with EFI use not only DOS partition system but also the GUID Partition Table (GPT). GPT disks are more reliable, support up to separate 128 partitions and use 64 bit LBA addressing.
DOS Partition tables exist in the MBR, the special part of disk which is located in the first sector of disk drive. You can also find DOS Partition tables in the first sector of the each extended partition.