What is style> tag in HTML?

The tag in HTML helps us to modify our text, viewed in the page. This modification includes changing font size, font family, font color etc. Not only the texts but also we can change the style of a body or part of a page. Now let’s look at various attributes of style and what else the tag supports.

Should style> tag be used in body>?

But to me it looks more and more like thoughtful use of in has already gone mainstream. Yes, you're right. As example I use tag in inside my plugin. Why, because it's easiest way to stylish plugin content. But one moment, all css classes are uniques for my plugin data.

Should style tag be included in head> of a document?

This has now been corrected to: "The element must be included inside the of the document. In general, it is better to put your styles in external stylesheets and apply them using elements." According to W3 standards, it is necessary to put style tag inside the head element of the document.

Can a HTML document contain multiple style> tags?

At w3schools it says: Each HTML document can contain multiple tags. But is it done this way ? You can put them anywhere, it will work. But it's best practice to have it in the head. And even better if it's an external css file. What you're creating there has far worse problems than simply a style element outside of the head.