EJS, what <%- %> mean?

Hello, while watching the node.js tutorial I bumped into something like this:
The person that was recording it created the views folder containing all .ejs files. In one of them, named login.ejs he put this code:

<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <!-- meta tags, links, scripts etc. -->
  </head>
  <body>
    <div class="container">
      <%- body %>
    </div>
  </body>
</html>

And in the others .ejs files he just wrote HTML code without html, body tags, so I of course came to conclusion that layout.ejs is template for others .ejs files where everything is put inside this <%- body %> place. However he hasn’t specified anywhere that other files shoud go there so I’m asking for more information about this <%- body %> element and where I can read about it more? I understand the basics of ejs but I can’t grasp what’s documentation of ejs is telling about this ‘strange’ element.