LOWER: It shows the entire word in lower case.
UPPER: The string is converted to all-caps.
INITCAP: The first letter of each word capitalised, and all other letters in lower case.
SELECT LOWER('ENGLAND') AS LOWER_VAL FROM dual; -- output: england
SELECT UPPER('England') AS upper_val FROM dual; -- output: ENGLAND
SELECT INITCAP('Once upon a time...') AS testvalue FROM dual; -- output: Once Upon A Time…