It converts the alpha character values into uppercase for the first letter of each word, keeping all other loetters in lower case.
Words are delimited by white spaces are characters that are not alphanumeric.

Syntax :

INITCAP(Column/Expression)

Examples :

1.
SELECT
'oracle corporation' string,
INITCAP('oracle corporation') initcap
FROM DUAL;

2.
SELECT Empno, INITCAP(Ename), Deptno
FROM EMP
WHERE = UPPER('blake');

3.
SELECT Ename, UPPER(Ename), LOWER(Ename), INITCAP(Ename)
FROM Emp;

4.
SELECT
'The job title for '||INITCAP(Ename)|| ' is '||LOWER(Job)
FROM Emp;