What is Difference between Portable and Platform independent language?

In portable language, code is written in one system and  if you want to reuse that code on other system then you must be transfer that higher language code to other system and execute that code at other system. You can not run object file(law level file to ) of one system to other system. Example, C language is portable language. In C language, code is written on one system and you want to used that code to the other system then you transfer that C language code(higher level code) to other system and execute at there.Here you can not able  run Object file of one system to other system.

But, In platform independent code, code is written one system and you want to reuse that code to other system than you can do using low level compile code, transfer that code to other system and simple execute that code. Example, Java is Platform Independent language. Code is written on one system and you want to used that code to other system , simple transfer byte code file of one system to other and execute that other system.

Simple term, In portable language you must be execute higher language code to their system individually but In platform independent language, No need of execute higher language code to their system individually, Only low level file is sufficient for execution of code.