in wikipedia it is possible to edit the text of an article in html.​
Help:HTML in wikitext The MediaWiki software, which drives Wikipedia, allows the use of a subset of HTML5 elements, or tags and their attributes, for presentation formatting.[1] But most HTML can be included by using equivalent wiki markup or templates; these are generally preferred within articles, as they are sometimes simpler for most editors and less intrusive in the editing window; but Wikipedia's Manual of Style recommends their use in certain cases. And HTML is useful outside of articles, for example for formatting within templates. For help with Cascading Style Sheet use within Wikipedia see Help:Cascading Style Sheets.
Constitutional amendment A constitutional amendment is a modification of the constitution of a nation or state. In many jurisdictions the text of the constitution itself is altered; in others the text is not changed, but the amendments change its effect. The method of modification is typically written into the constitution itself.