title: Parallelism in Julia: Native Threading Support
body: <p>In their <a href="http://arxiv.org/abs/1209.5145" rel="noreferrer">arXiv paper</a>, the original authors of Julia mention the following: </p>
  
  <blockquote>
    <p><code>2.14 Parallelism</code>. 
    Parallel execution is provided by a message-based multi-processing system implemented in Julia in the standard library.
    The language design supports the implementation of such libraries by
    providing symmetric coroutines, which can also be thought of as
    cooperatively scheduled threads. This feature allows asynchronous
    communication to be hidden inside libraries, rather than requiring the
    user to set up callbacks. <strong>Julia does not currently support native
    threads, which is a limitation, but has the advantage of avoiding the
    complexities of synchronized use of shared memory.</strong></p>
  </blockquote>
  
  <p>What do they mean by saying that Julia does not support <strong>native threads</strong>? What is a native thread?</p>
  
  <p>Do other interpreted languages such as <strong>Python</strong> or <strong>R</strong> support this type of parallelism? Is Julia alone in this?</p>