HTML helpers are methods used to render HTML elements in a view. They are part of the System.Web.Mvc.HtmlHelper namespace.

There are different types of HTML helpers:

Standard HTML Helpers: They are used to render normal HTML elements, e.g. Html.TextBox().

Strongly Typed HTML Helpers: These helpers render HTML elements based on model properties, e.g. Html.TextBoxFor().

Custom HTML Helpers: The user can create custom helper method which returns MvcHtmlString.