FOR loop in the dos box

Print all files ending in .html in the current directory:

for %i in (*.html) do @echo %i

The following for loop renames all files with the suffix foo in files with the suffix bar.
This works with the ~n idiom that is a file's name without suffix.

for %i in (*.foo) do move %i %~ni.bar

Assign the current time to %t and echo %t:

for /f %t in ('time /t') do @echo it's %t, now

Recursively print all *html files:

for /f %h in ('dir /s /b *.html') do @echo %h