UPPERCASE to lowercase command?
 

Is there a bash command to convert a word that contains a couple of uppercase letters to an all lowercase letters word?

Like converting "TeSt" to "test"

Maybe 'sed' or 'tr' ???

yep tr will do it fine, there are at least three examples of case converting in the info documentation for tr.

you could do it in sed but not easily.

Did you do man tr at all?????

$ echo "TesT" | tr [:upper:] [:lower:]
test

Or using sed

$echo "TesT" | sed 'y/abcdefghijklmnopqrstuvwxyz/ABCDEFGHIJKLMNOPQRSTUVWXYZ/'
TEST

You can use awk. Just pipe your string into:
awk {'print tolower($_)'}

eg:
echo TeSt | awk {'print tolower($_)'}

linux@linux:~> echo TeSt |sed 's/\(.*\)/\L\1/'
test