Holes in the file system
I am doing a research in linux. Now only i have started learning linux and i have a doubt in linux file systems. What is the purpose of holes in filesystem. Why do we need that. They say that it takes bit less disk space and again they say that
"Holes are implemented by storing a special value as the address of the data block in the indirect block or inode. This special address means that no data block is allocated for that part of the file, ergo, there is a hole in the file."
What is the meaning of above lines. I got from some linux tutorial website.