Sybex CSG 11 page 55 (Kindle version)

[Corneliu Josan]

In the "TABLE 2.3 Default initialization values by type" it is mentioned that all numeric types: byte, short, int, long have default value 0. But the default value for long type is 0L and not 0. And for float and double is 0.0f and 0.0d, not just 0.0. (https://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html)

[Scott Selikoff]

0 is 0.  0f and 0L is just the style of writing the literal for the compiler so it knows how to interpret it.  I promise the exam will never ask you the difference between 0L and 0!