title: What is the difference between "be_true" and "be true" in RSpec
body: <p>Can any one please explain me about the difference between <code>be_true</code> and <code>be true</code> in Ruby with simple example.  I have also seen <code>be_true</code> and <code>be_false</code> are changed to <code>be_truthy</code> and <code>be_falsey</code></p>
  
  <p>I have an example where <code>'be true'</code> worked, but when I tried to use <code>'be_true'</code> or <code>'be_truthy'</code> spec failed.</p>
  
  <p>I am using RSpec version 3.1.7</p>