Struts 2 comes with three built-in themes −

simple theme − A minimal theme with no "bells and whistles". For example, the TEXTFIELD TAG renders the HTML <input/> tag without a label, validation, error reporting, or any other formatting or functionality.

xhtml theme − This is the default theme used by Struts 2 and provides all the basics that the simple theme provides and adds several FEATURES like standard two-column table layout for the HTML, LABELS for each of the HTML, Validation and error reporting etc.

css_xhtml theme − This theme provides all the basics that the simple theme provides and adds several features like standard two-column CSS-based layout, using <div> for the HTML Struts Tags, Labels for each of the HTML Struts Tags, placed according to the CSS stylesheet.

Struts 2 comes with three built-in themes −

simple theme − A minimal theme with no "bells and whistles". For example, the textfield tag renders the HTML <input/> tag without a label, validation, error reporting, or any other formatting or functionality.

xhtml theme − This is the default theme used by Struts 2 and provides all the basics that the simple theme provides and adds several features like standard two-column table layout for the HTML, Labels for each of the HTML, Validation and error reporting etc.

css_xhtml theme − This theme provides all the basics that the simple theme provides and adds several features like standard two-column CSS-based layout, using <div> for the HTML Struts Tags, Labels for each of the HTML Struts Tags, placed according to the CSS stylesheet.