In WordPress, excerpt is a term used in reference to a summary or part of an article with a link to the full article. More content can be displayed in less space with the use of excerpts. This becomes markedly useful for content-rich websites (e.g., magazine and news sites) where website owners want to highlight more content on the main page with links to full articles. Search pages, archived pages, and RSS feeds are examples of sites that generally use excerpts.
There are 3 different types of website excerpts: 1) Automated Excerpt. This gets auto-generated directly from post content, 2) <!–more–> tag excerpt. This is also auto-generated and uses the content up to the specified part where this tag is inserted. And 3) Manual Excerpt. This is entered by the user separately in the post.
Excerpts can be auto-generated either by using the <!–more–> tag in the content of the post, or by a WordPress theme. You can also generate an excerpt in WordPress by entering the content for the excerpt in the Excerpt field on Post Edit screen. As this field is not shown by default in the post edit screen, you must enable it. To do this, you must go to the post edit screen in the top right corner and click on the Screen Options button, then enable it.
Depending on how they are used, excerpts can be automated, as well. Excerpts that are automated usually extract a portion of the post that falls within the specified word count, which is 55 words by default. However, this can be manually changed. In general, unless a manually changed word count has been provided for a given post, an excerpt is automatically generated within the 55-word limit.