list of current files “test-file1.txt test-file2.txt  test-file3.txt  test-file4.txt”

change .txt to .html with rename

rename .txt .html *.txt

new list “test-file1.html  test-file2.html  test-file3.html  test-file4.html”

or use a for loop

for i in *.txt; do mv "$i" "$(basename $i .txt).html"; done OR for i in *.txt; do mv "$i" "`basename $i .txt`.html"; done

Add a prefix to every filename

for f in *.txt ; do mv "$f" "PREFIX_$f" ; done

new list “PREFIX_test-file1.txt  PREFIX_test-file2.txt  PREFIX_test-file3.txt  PREFIX_test-file4.txt”

Add a suffix

for f in *.txt ; do mv "$f" "$f_SUFFIX" ; done

Remove the PREFIX_ from every filename, adjust the cut command accordingly

for name in PREFIX_* ; do newname="$(echo "$name" | cut -b8-)"; mv "$name" "$newname" ; done

new list “test-file1.txt  test-file2.txt  test-file3.txt  test-file4.txt”

Remove the extension from file names

for i in $(ls); do mv $i ${i%.*}; done

Remove a prefix from file names

for i in $(ls *.txt); do mv $i ${i#*-};done

using a for loop and mv

for file in $(ls); do mv -i "${file}" "${file/Disc_1_-_/}"; done

this

Disc_1_-_01_-_Bright_Side_of_the_Road.m4a
Disc_1_-_02_-_Gloria.m4a
Disc_1_-_03_-_Moondance.m4a
Disc_1_-_04_-_Baby_Please_Don_t_Go.m4a

becomes

01_-_Bright_Side_of_the_Road.m4a
02_-_Gloria.m4a
03_-_Moondance.m4a
04_-_Baby_Please_Don_t_Go.m4a