PRACTICE OF TESTING COMPONENTS OF A PROGRAM AUTOMATICALLY

HOW DO YOU KNOW SOMETHING IS WORKING AS DESIGNED

ENSURE THAT CHANGES DON'T BREAK THINGS THAT WORKED BEFORE

DEFINE OR UNDERSTAND WHAT SOMETHING IS SUPPOSED TO DO

WHEN YOU'RE DEBUGGING, REFACTORING OR MAKING BIG CHANGES

IT MAY NOT BE RIGHT, BUT IT'S BETTER BECAUSE PARTIALLY TESTED

AN IMPERFECT TEST TODAY IS BETTER THAN A PERFECT TEST SOMEDAY