linux-cli-find

find . -maxdepth 1 -type f -name "[[:upper:]]*"
find . -maxdepth 1 -type f -name "[[:upper:]]*" -exec mv -t umsortieren/ {} \+
 
# Remove empty folders
find . -empty -type d -delete
 
# rm & find
find . -type f -name foo\* -exec rm {} \;
find  . -name 'name*' -exec rm {} \;
rm -f $(find . -maxdepth 1 -type f -name "*" ! -name "important.txt") # Delete all but one

Replace dots with dashes in dendron-style file names

find ~/zettel -name "*.md" -print0 | while IFS= read -r -d '' f; do mv "$f" "$(dirname $f)/$(basename $f .md | tr '.' '-').md" ; done

Delete everything in folder, including hidden files and folders (avoids rm -rf .* *)

find $directory -mindepth 1 -delete