🚀 go-pugleaf

Below are six terms that I thought I understood, but recently 
have heard used in ways that are different from my 
understanding. They were used by people who seemed to be very 
knowledgeable. These terms are as follows:

1. Platform:

The way I've understood this concept, is that a platform is the 
combination of a computer and an operating system, i.e. a PC 
running Windows is a platform, a PC running UNIX is a platform, 
a workstation running Unix is a platform. At one of the Borland 
conferences, one of the platform seminars was about Java. Has 
the ability of Java to run on any platform meant that it has 
become a platform? Java can't run a program written in C.

2. Syntax:

  I also heard an operating system described as having the 
ability to run applications (development tools) of different 
syntaxes. I thought a syntax was something like ASN.1. Would C++ 
on a Windows platform be described as having a different syntax 
from C++ on a Linux platform. 

3. Application:

Also, the way I've understood it is that a development tool (see 
second line of above paragraph) is a utility that is used to 
create an application, i.e. Jbuilder 4.0 can be used to create a 
Java application. In other words, the final product is the 
application, not the development tool.

4. Operating system (interface): 

Would an operating system that could handle different syntaxes 
(assuming a syntax was a slightly different version of the same 
language), have any utility, even in theory? In other words, if 
a program--originally written in C to run on, for example, a Mac-
-could also run on a PC with a theoretical operating system 
(call it operating system X) that provided a common interface, 
would this do any good? If it would, is the word interface used 
in its proper context? I didn't know that an interface is almost 
synonymous with operating system.

5. Portability:

I thought the attempts at a universal operating system, i.e. 
Unix, and universal languages, i.e. Java, ADA, have covered this 
ground about as much as it can be, and that the Unix operating 
system(s) and the ADA language never really did become portable, 
but Java actually came pretty close, although it still requires 
native methods.

It almost sounds like this idea (described in 4. above) is 
portability in reverse. Build a platform, and they will come. Is 
the idea of an operating system that runs different syntaxes a 
legitimite idea, even in theory? Wouldn't the operating system 
also have to be portable, and  even then, wouldn't it also have 
to capture or find a sizable market niche to do anything?

6. API:

Finally, what is an API? I thought that an application program 
interface (API) was the methods and data of a class or interface 
that was included in the Java SDK, or Java Beans. In other 
words each class or interface (in the library) had its own API. 
Recently I've heard API referred in the context of a whole 
package, like Java Beans, (e.g. the Java Beans API), or even in 
the context of a browser, i.e. Netscape, providing an API.