Are all C programs C++ programs?

That depends on what you define as a "C program" and what you define as a "C++ program".

All C code will compile and run with C++ compilers, because C code is a subset of C++ code, but some purists would say that even though the code compiles and runs, it doesn't constitute a C++ program because it's not using, for instance, C++ input and output. C uses functions such as scanf(), gets() and printf(), while C++ uses stream classes and the << and >> operators.

But I'm more liberal and would answer your question with a "Yes".

Hope that helps.

For the most part C++ includes full support for C. It was designed this way intentionally.

from wiki:

C++ is often considered to be a superset of C, but this is not strictly true.[21] Most C code can easily be made to compile correctly in C++, but there are a few differences that cause some valid C code to be invalid in C++, or to behave differently in C++.

the C++ standard states:

In addition to the facilities provided by C, C++ provides additional data

types, classes, templates, exceptions, namespaces, inline functions, operator overloading, function name overloading, references, free store management operators, and additional library facilities.

http://www.open-std.org/jtc1/sc22/wg21/docs/papers...

So basically, this states that C++ is C plus a bunch of other stuff.

A C++ compiler, with a few exceptions, can handle straight C. A strictly C compiler would not be able to deal with C++.

Not anymore, at one time C++ was just an extension of C. Since then, C has changed, and so has C++.

However that being said it's not unusual for the same program to compile both C and C++. The method is the same, but there are just some differences int he libraries that you need the compiler to link to.

No, this is not true.

It is only true that many simple C programs can be compiled by a C++ compiler and will execute in the same manner.

But many other C programs will fail to compile by a C++ compiler.

And some C programs will be compiled by a C++ compiler, but the results of their execution will be totally different, for example if they use sizeof('a') in a calculation.

C++ and C share a common subset.

I guess your trying to say is C++ a sequel to C?

And can C++ language be translated to C and vice versa.

First you have to know that the creator of C did not make C++.

They are two different languages. Just very similar

C++ was inspired by C.

You probably already know this. But there are also other C type variates. Example C# C-- Objective-C.

Did you know C was inspired by B?

To answer the second part.

C++ was created because C and other procedure-oriented languages could not address the complex problems that are present in real life. So the question of translating C++ code to C is absurd. You have to rewrite the code completely and that would be no small feat.

So no you cannot traslate C++ to C.

Thats exactly correct, C was created before C++. C++ was basically the same language with more features and tools. Though a C compiler won't recognize all of the new code that C++ offers.