Ruby on Rails: How do I add placeholder text to a f.text_field?

Question

How can I add placeholder text to my f.text_field fields so that the text comes pre-written by default, and when a user click inside the fields, the te

Answer 1

In Rails 4(Using HAML):

=f.text_field :first_name, class: 'form-control', autofocus: true, placeholder: 'First Name'