API is your organ.
There are countless classes in API
Every time, when the new program form will be made,
New API is made, too.
API in JAVA, API of Servlet and API of android
Your program is written by a JAVA language.
That's changed to inter-language.
A virtual machine carries out with it.
JAVA (JRE) of Windows and JAVA (JRE) in LINUX.
A program of inter-language is executed at these JRE.
What of a creature should this be compared to?
There are various languages in the world,
They are changed to the same inter-language at machine translation.
It's understood with it.
I think Mechanism of such machine translation is similar to JAVA .
Programs of JAVA, what are you?