title: Can a blockchain be Centralised? Will it be called as Blockchain if it is centralised?
body: <p>I was reading lot of articles on blockchain and almost everyone has some different understanding of blockchain.<br>
  Is there any accepted definition of Blockchain by any community?  </p>
  
  <p>In few articles I read:  </p>
  
  <ul>
  <li><p>Blockchains are Decentralised while DLTs are not.  </p></li>
  <li><p>All blockchains are DLT but not all DLTs are blockchain. It added "if transactions get stored in blocks then it is a blockchain else it is not"  </p></li>
  </ul>
  
  <p>From above statements-<br>
  Is Decentralisation must for a Blockchain?<br>
  Or it is just a Immutable Distributed Database? which can be centralised or decentralised?</p>