Using partial file

View filename that starts with underscore are called partial:

• _form.html.erb
• _nav.html.erb

When using render function, we specify the partial name without the underscore:

<%= render 'nav' %>

If the partial file is not in the same folder, say views/layouts/_nav.html.erb, we can include the path.

<%= render 'layouts/nav' %>

Sometimes we need to pass variable into partial. We can do that by specifing the locals.

<%= render partial: 'layouts/nav', locals: {key: 'value'} %>

What’s next? We’re going to take a look at “Dynamic title with content for”.