title: Visio: Many database notation for designing a database
body: <p>I am learning database design and trying to model using Visio 2013. When I want to create database model, I came across the following database notation in Visio 2013:</p>
  
  <blockquote>
    <p>1) Crow's Foot database notation<br>
    2) Chen's database notation<br>
    3)
    UML database notation<br>
    4) IDEF1X database notation</p>
  </blockquote>
  
  <p>Why do we have many notations for designing a database and among them is the one that is being widely used in real database design?</p>
  
  <p>Can anyone help me get this doubt clarified?</p>