What is the meaning of "_tag" for Rails form helpers?

Tag helpers are not model-specific, as described here:

http://guides.rubyonrails.org/form_helpers.html#dealing-with-model-objects-model-object-helpers

"The most common task for a form is to edit or create a model object. While the * _tag helpers can be used for this task, they are somewhat verbose because for each tag you need to provide the correct parameter name and set the default input accordingly. Rails provides helpers adapted to this task. These helpers do not have the _tag suffix, such as text_field, text_area. "