title: what is difference between Orderer validating and peer validation before commit block
body: <p>I have query, i am reading the hyperledger fabric article, In article its mention that, User <em>User1</em> sends a transaction <em>Tx1</em> to Peer <em>P1</em>, Peer <em>P1</em> endose <em>E1</em>, the transaction <em>Tx1</em>, the transaction received back to <em>user1</em> and he pass it to order <em>or1</em>, And order will validate the <em>Tx1</em> and create the block and it will commit. </p>
  
  <p>My Question is :</p>
  
  <pre><code>  1. when order is committing the block, why it will send to peer P1 back.
    2. In article they mention Peer P1 is also validate Tx1, How Peer will 
       verify the Tx1.
    3. If Peer P1 verify the Tx1, does Peer P1 also keep the record of all the Peers and Orderer details.
    4. If Peer also can Validate the Tx1, best thing is to apply the 
      block/Batch creation mechanism to Peer directly, so no need of orderer. i have doubt please suggest me.
  </code></pre>