In Linux or Unix based OS create file into two parts ::

1. Data part : it contains the information regarding the iNode number of the file along with the variuos permission on that file.

2. Filename part : contains the name of file and inode number of the file.

What is a HardLink : If two filenames point to same iNode number than those files are said to be hardlinked. To create a HardLink linux uses following command-

ln 'path/of/file/to/create/hardlinkof' 'path/where/to/create/hardlink'  

The problem with hardlinks is that :

1. it can only work for the files that are in  same file system.

2. The file which has to be hardlinked must preexist .

3. Hardlinks doesnot work upon directories.

On the other hand Softlinks can be described as a file whose data part contains path to another file. Softlinks overcome the problems of hardlinks mentioned above.

ln -s 'path/of/file/to/create/hardlinkof' 'path/where/to/create/hardlink'