Final answer:
Single, double, and triple indirect blocks are mechanisms used in file systems to address large files efficiently by extending the range of addresses beyond the limits of direct block pointers in an inode.
Step-by-step explanation:
Single, double, and triple indirect blocks are used in file systems to efficiently manage disk space when index addressing files. Each type serves to extend the range of addresses that can be referenced for large files.
Single Indirect Blocks
With single indirect blocks, a file's inode points to an indirect block instead of direct data blocks. The indirect block contains a list of pointers to actual data blocks. This allows for extension beyond the fixed number of direct block addresses in an inode.
Double Indirect Blocks
As file size increases, double indirect blocks become necessary. An inode points to a double indirect block that contains pointers to multiple single indirect blocks, which in turn point to actual data blocks.
Triple Indirect Blocks
For even larger files, triple indirect blocks are used. An inode points to a triple indirect block. This block points to double indirect blocks, which link to single indirect blocks, thus exponentially increasing the number of addressable blocks.