title: Many questions about the various C++ compilers available to me on OS X
body: <p>I am having trouble understanding the different compilers that are available to me. </p>
  
  <p>I mainly use Xcode for writing and compiling, and in Xcode's preferences, there are all of these options for C++ compilation:</p>
  
  <p>C++ Language Dialect: </p>
  
  <ul>
  <li>C++98[-std=c++98] through C++14[-std=c++14]</li>
  <li>GNU++98[-std=gnu++98] through GNU++14[-std=gnu++14]</li>
  </ul>
  
  <p>C++ Standard Library:</p>
  
  <ul>
  <li>libstdc++ (GNU C++ standard library)</li>
  <li><p>libc++ (LLVM C++ standard library with C++11 support)</p>
  
  <ol>
  <li><p>Can someone explain what exactly all of that ^ is? </p></li>
  <li><p>I understand that (and correct me if I'm wrong), that apple no longer distributes GCC with Xcode and use Clang instead? </p></li>
  <li><p>If that were the case, then why does Xcode have the option for GNU C++ standard library? Doesn't GNU make GCC? </p></li>
  <li><p>What compiler is invoked when I run C++ code in my local terminal with <code>g++ filename.cpp</code>? </p></li>
  <li><p>Is there any way to make sure that this <code>g++</code> "compiler" is up to date?</p></li>
  <li><p>What's the difference between compiling with <code>g++</code> in the terminal and using Xcode?</p></li>
  <li><p>Also, what would be the difference if I tried running C++ programs with Clang?</p></li>
  <li><p>My class requires us to test our programs on the department's server's compiler via ssh from my terminal. The server is a Unix machine and I know that its compiler is GNU's GCC compiler and we also access it using <code>g++</code>. Does this mean that the local <code>g++</code> in my terminal is also GCC?</p></li>
  </ol></li>
  </ul>
  
  <p>edit: Grammar</p>