div标记内的HTML div标记的用途是什么？

Question

i am new to HTML and i am struggling to understand when and specifically why we use a div inside a div.For example:

 <section id="home-bg-parallax" class="h-100 overflow-hidden p-0 w-100">
 <!-- BG Parallax -->
 <div class="bg-parallax bg-overlay-black-8"></div>

 <div class="h-100 left-0 position-absolute top-0 w-100">
 <div class="container h-100">
 <div class="row align-items-center h-100">
 <div class="col-lg-9 col-xl-9">
 <span class="font-alt font-w-600 opacity-9-5 letter-spacing-2 text-large 
 text-uppercase text-white">Welcome To Traversy Media</span>

 <h2 class="font-alt font-w-700 letter-spacing-2 m-0 mt-3 text-uppercase 
 text-white title-xs-extra-large title-sm-extra-large-3 title-extra-large- 
 4">
 Web Development Tutorials & Courses
 </h2>



<span class="bg-base-color d-block mt-4 sep-line-extra-thick-long"></span>
</div>
<!-- //.col-lg-9 -->
</div>
<!-- //.row -->
</div>
<!-- //.container -->
</div>
<!-- //.h-100 -->
</section>

This is code from TraversyMedia.com.Maybe this question is dumb but i cannot figure out why we do this.If somebody can help me,i would be grateful.

Answer 1

如果元素全部共享一种样式或需要相对于它们所在的div定位，则使用不同的div标签将它们组合在一起。例如，您的网页标题栏可能有一个div，但随后另一个div，这样您就可以调整标题的导航部分而不是整个标题。