Change in all directory tree one string for another using find and sed

change_ocurrences.md

From http://stackoverflow.com/questions/6758963/find-and-replace-with-sed-in-directory-and-sub-directories

find ./ -type f -exec sed -i -e 's/apple/orange/g' {} \;

This changes all ocurrences of apple to orange in the folder and subfolders from "."