Every HTML web page is split into different parts using the <div> tag. For instance, you can break the body (<body>) of your website into several sections such as navigation, header, main content, sidebar and footer amongst others.
Once you have your web page in sections, you can order (or arrange) the sections as you wish using CSS. This process is known as styling, and it involves adding other style elements such as color, size, borders, special effects etc. Such is the power of CSS, which – by the way – is short for Cascading Style Sheets. When you put your HTMl and CSS files together and throw in a couple of images, you end up with a complete website.
Static HTML web pages are split into divisions (what we called sections earlier on) using <div> tags (or tables if you’re really old school). On the other hand, WordPress themes are split into different php files, which are then put back together using template tags.
Therefore, instead of having all body elements (header, main content, sidebar, footer etc) living in a single file (as is the case with static HTML), each of the body elements (in WordPress themes) lives in a separate files.
So, the header will live in header.php, the sidebar will find home in sidebar.php, the main content will live in index.php, or single.php (if it’s a post) or page.php (if it’s a page). The footer section will live in footer.php and so on.
Are you following? Check out the illustration below:
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