based on preparation of: dwaves.de/2017/04/26/linux-bash-searching-and-colorful-highlighting-of-text-patterns-in-files-with-grep-regular-expressions/

wc -w; # basically starting wc in "interactive" mode, quit with Ctrg+Z
joe is very hungry today
5

wc -w < termine; # word count, count the words in that file
10

cat artikel.txt termine | wc -w; # count words of two files artikel.txt and termine
29

user@suse:~> cat a* termine | wc -w; # count all words of all files in the current directory that start with an "a" but also all words in termine (same result)
29

cat << EOF; # instead of Ctrl+Z when typing EOF and hitting enter it runs the command and quits the program
> hello
> here it is
> warm
> EOF
hello
here it is
warm

cat << EOF > editor_for_poor.txt; # starts cat in interactive mode, creates a file and writes to that file
> this was written
> with a very cheap editor
> EOF
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