grep without filenames

I needed to grep a directory, and sub directories, and not displaying the filenames in the output. This is when the man page came to the rescue.

man grep | grep filename  

Output

-H, --with-filename  
-h, --no-filename  

There we go, -h, --no-filename, is what I needed.

Example with output to a file:

grep -r "searching-for-this" . --no-filename > /tmp/test.txt