Linux CAT Command Examples

This was a solid reference:

https://www.howtogeek.com/278599/how-to-combine-text-files-using-the-cat-command-in-linux/

cat file1.txt file2.txt file3.txt > file4.txt

cat file1.txt file2.txt file3.txt | sort > file4.txt

https://stackoverflow.com/questions/4969641/how-to-append-one-file-to-another-in-linux-from-the-shell