title: how to operate AJAX by axios with react
body: <p>I'm new to use <code>axios</code> with <code>react</code> so, I want to ask some questions.</p>
  
  <p>Let me explain what I want to make first.</p>
  
  <p>Someone(<strong>A</strong>)  clicks <code>likes</code> button about Someone(<strong>B</strong>)'s post and (<strong>B</strong>) will get a notification because of <code>+1 likes</code> by <code>axios</code> after few seconds.</p>
  
  <p>I wonder how these processes exactly is going?
  I think clicking <code>likes</code> button by (<strong>A</strong>) makes the number of (<strong>B</strong>)'s <code>likes</code> in <code>DATABASE</code> changed, but How (<strong>B</strong>) get this updated number of <code>likes</code>?? I understand that if (<strong>B</strong>)'s page is refreshed, (<strong>B</strong>) will get the updated number of <code>likes</code>. </p>
  
  <p>However, Without F5(refresh), how (<strong>B</strong>) get the updated number of <code>likes</code> by <code>axios</code>?? Does <code>axios</code> check every seconds whether the data from <code>DATABASE</code> is changed or not? </p>
  
  <p>Or it is related with <code>redux</code>?</p>