Shortcode is a piece of Code used in WordPress post types to embed pre-defined PHP functions into the post.
Shortcode is a special tag that you can add to a WordPress post or page that allows you to display dynamic content, without needing to know any coding. It is a WordPress-specific code that lets you add custom functionality to your pages and posts.
For instance, you can use a shortcode to display the latest blog posts, an image gallery, or a contact form. Instead of writing code to display these elements, you can simply add the shortcode to the post or page where you want the content to appear.
Shortcodes are enclosed in square brackets  and typically begin with the word “shortcode,” followed by a parameter that tells WordPress what to do with the content. The content inside the shortcode is parsed by WordPress and replaced with the dynamic output, based on the parameters passed to the shortcode.