title: Does each user only have 1 session id?
body: <p>I'm still a beginner in using sessions and cookies and I don't understand this, so I want to ask:</p>
  
  <p><strong>1. Does each user only have 1 Session ID?</strong> </p>
  
  <p><strong>2. What is a Session ID?</strong></p>
  
  <p>I tried to store data in session, but when I tried to store other data it had a same <code>Session ID</code>. So how do I know who this data belongs to?</p>
  
  <p>I actually want to make a shopping cart in react.js SPA using backend express. but i dont know how to store this data cart. so far what I have done I want to save the data cart into a session, like <code>product_id and product_variant</code>and then call this <code>product_id and product_variant</code> in database based on this <code>Session ID</code>. </p>
  
  <blockquote>
    <p>Correct Me If I'm Wrong. Thanks</p>
  </blockquote>