title: Default behavior of "git push" without a branch specified
body: <p>I use the following command to push to my remote branch:</p>
  
  <pre><code>git push origin sandbox
  </code></pre>
  
  <p>If I say</p>
  
  <pre><code>git push origin
  </code></pre>
  
  <p>does that push changes in my other branches too, or does it only update my current branch? I have three branches: <code>master</code>, <code>production</code> and <code>sandbox</code>.</p>
  
  <p>The <code>git push</code> documentation is not very clear about this, so I'd like to clarify this for good.</p>
  
  <p>Which branches and remotes do the following <code>git push</code> commands update exactly?</p>
  
  <pre><code>git push 
  git push origin
  </code></pre>
  
  <p><code>origin</code> above is a remote.</p>
  
  <p>I understand that <code>git push [remote] [branch]</code> will push only that branch to the remote.</p>