While editing a file you will find a few unwanted spaces at the end of line or at the beginning of the lines. You can get rid of these unwanted whitespace using vi/vim.
Commands to remove unwanted whitespace
Many of you might be aware of the search option in vi/vim command mode. In search, \s finds whitespace (a space or a tab), and \+ finds one or more occurrences.
You can use the following vi/vim command to delete trailing whitespace at the end of each line:
And, the following command can be used to delete whitespace at the beginning of each line: