title: npm install bower using -g vs --save-dev
body: <p>I'm new to node and using npm to both do some node, angular and Express tutorials. I have used bower before in a tutorial. I'm pretty sure I have installed it using -g already as when i run the  <code>bower -v</code> command I get back <code>1.3.3</code> I am to understand that installing it using -g means, <em>Install this globally so that on the next project I don't have to install it again</em>. </p>
  
  <p><strong>1) Is this correct?</strong> </p>
  
  <p><strong>2) When I start working with a new project do I have to initialize bower?</strong></p>
  
  <p><strong>3) Is there any reason I should use <code>install bower --save-dev</code> after I have already installed bower (-g)lobally?</strong></p>
  
  <p><strong>4) What exactly does <code>install bower --save-dev</code> do?</strong></p>
  
  <p>I have searched and get nothing on google or stack over flow when I search "--save-dev".</p>
  
  <p>I really want to understand this and if you help me, it will help me understand installing much more than just bower and how to use those installs. Again, I'm new to the command line for this type of development and new to these technologies, but have some basic understanding.</p>