title: Moment js: What is the different between moment(date:string, format:string) to moment(date:string).format(format:string)?
body: <p>I want to know what is the different between:</p>
  <blockquote>
  <p>moment('2021-12-12', 'YYYY-MM-DD')</p>
  </blockquote>
  <p>to this one:</p>
  <blockquote>
  <p>moment('2021-12-12).format('YYYY-MM-DD)</p>
  </blockquote>