Find files not containing search string

Question

Is there a way to find out files of a type ,NOT containing a particular key-word.
This is both -
1. under a particular directory
2. Under and particular directory and all underlying subdirectories.
Help is appreciated

Answer 1

Read the documentation of GNU grep

You probably want

grep -L word file*

or

grep -Lr word dir/

Answer 2

You could achieve this by something like

grep -L keyword $( find /start/path -type f )

You may need GNU grep for -L .