What is the difference between “architecture-neutral” and “portable”?

Question

I\'m reading Herbert Schildt\'s book \"Java: The Complete Reference\" and there he writes that Java is portable AND architecture-neutral. What is the difference between this

Answer 1

I suspect that he means that code can run on many platforms without recompilation. It is also possible to write code that deals with the underlying system without rewrites or conditions.

E.g. Serialized objects from a 32 bit Windows system can be read on a 64bit Linux system.