What is the significance of "ORDER BY" in the following MySQL statement?

SELECT emp_id, fname, lnameFROM personORDER BY emp_id;

SELECT emp_id, fname, lnameFROM personORDER BY emp_id DESC;

SELECT emp_id, fname, lnameFROM personORDER BY emp_id ASC;

SELECT d.name, COUNT (emp_id) emp_noFROM department d INNER JOIN Employee eON d.dept_id=e.emp_idGROUP BY d.nameHAVING COUNT (emp_id)>2

SELECT emp_id, emp_nameFROM personORDER BY emp_id, emp_name;

SELECT emp_id, fname, lnameFROM accountWHERE start_date

SELECT emp_id, title, start_date, fname, fed_idFROM personORDER BY 2, 5;

SELECT emp_id, title, start_date, fname, fed_idFROM personORDER BY RIGHT (fed_id, 3);

SELECT emp_id, title, start_date, fname, fed_idFROM personORDER BY LEFT (fed_id, 3);

SELECT emp_id, ‘ACTIVE’, emp_id * 3.145, UPPER (lname) FROM Employee;

SELECT emp_id,‘ACTIVE’ AS STATUS,emp_id * 3.14 AS emp_pi,UPPER (lname) AS last_nameFROM employee;