difference between text_field and text_area in form_for

Question

So I have seen examples of text_field and text_area being used in forms like this:

<%= form_for :account do |a| %>
    Name: <%= a.text_field :name %><br />
    Password: <%= a.text_area :password %><br />
    Password Confirmation: <%= a.text_field :password_confirmation %><br />
<%= a.submit %>
<% end %> 

I don't understand the difference, though. Is it necessary for a beginner Rails developer to understand the difference?

I found some explanations in the API which I don't understand - perhaps somebody can take a look and let me know what is going on.

For "text_area":

text_area(object_name, method, options = {})

Returns a textarea opening and closing tag set tailored for accessing a 
specified attribute (identified by method) on an object assigned to the template 
(identified by object). 
 Additional options on the input tag can be passed as a hash with options.

Then, for "text_field":

  text_field(object_name, method, options = {}) Link

    Returns an input tag of the “text” type tailored for accessing a specified 
attribute (identified by method) on an object assigned to the template 
(identified by object). Additional options on the input tag can be passed 
as a hash with options. These options will be tagged onto the HTML as an 
HTML element attribute as in the example shown.

Answer 1

a.text_field :name is parse to the following html

<input type="text" name="name">

a.text_area :name would parse to something like:

<textarea rows="4" cols="50">

</textarea>

depending on the options passed.

The simplest way of looking at it is text_field gives you a place for a single line of text, where text_area gives an area for multiple lines.

you can pass a hash of options to the text_area helper to specify the number of rows and columns.

In the example you give above, it would be poor practice to use either text_field or text_area for passwords, you'd be better to use a.password_field