So you might think dw (delete word) does the job, because it often does, actually. However, in Unix environments you might also interpret a word in a different way, e.g. a "/path/to/file" can be seen as just one word in terms of the number of arguments. In that case, "dw" will not delete "/path/to/file", instead it will interpret every slash "/" as a separate word, so you have to enter "dw" 6 times. You can easily adapt this style of deleting "words" by replacing space by your own character. Maybe you want to delete a whole sentence, then you want to type "df.". There are many thinkable usages.