Bootstrap's utility and layout classes provide you with everything you need to style a responsive webpage. With Tailwind, however, you are much more involved in styling the webpage because you end up having to create your own components using the utility classes that the framework offers. So, the main difference between bootstrap and tailwind is UI (User Interface).

The CSS Box Model is the primary means of layout for everything on the web. It is a standard created by the World Wide Web Consortium which describes layout as rectangular boxes in html which surround every single element on a web page or in the document tree. Using the box model, web designers and developers can make use of various properties such as padding, borders, margin, and many others to create page layouts.

One of the most important features of HTML5 is its semantics. Semantic HTML refers to syntax that makes the HTML more comprehensible by better defining the different sections and layout of web pages. It makes web pages more informative and adaptable, allowing browsers and search engines to better interpret content. For example, instead of using div id="header" you can use a header tag.