It is best to use meaningful tags of HTML5 and try to be consistent in different and older versions of browsers, otherwise you will find that the screen is full of divs and you will need to code later Validation, modification and lookup are a disaster.
Moreover, when writing code, in order to facilitate the reuse of the code in the future and the background construction of the back-end PHP and JSP personnel, code comments are indispensable. It is still necessary to study more websites with good code layout.