title: what does transaction mean in reference with neo4j database
body: <p>I got a bit confuse with term transaction.
  Suppose in transaction A we have two commands C1 and C2 and same in transaction B.
  Now both transaction come at same time then 
  Are these observations correct?</p>
  
  <ol>
  <li><p>All commands of transaction A C1 and C2 will be done first (assuming A enter first) , then only commands of transaction B will be executed.</p></li>
  <li><p>Any command of transaction A or B can be executed but with assurance that If any of the command fails of any of the transaction then that transaction will be rollback.</p></li>
  <li><p>If second case is true then in transaction by default, it do not lock any resource until its completion </p></li>
  <li><p>If first case is true then by default transaction hold lock on resources until their completion.</p></li>
  </ol>
  
  <p>thanks </p>
  
  <p>Amit Aggarwal </p>