Changing the Full Post Content to an Excerpt
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Some wordpress themes display the full content on the main page. So to change it to show just excerpt of articles, edit the appropriate template files with the built-in Theme Editor (Presentation > Theme Editor) or any text editor and search for the_content() and change it to the_excerpt().
By default, WordPress shows only the first 120 words or so of a post as the excerpt. It also strips out all links, styles, and tags so only the text appears. The lazy man’s way. 🙂
CAUTION:
Do NOT change it in your single.php
or page.php
, if you have them in your Theme, as that will force only the excerpt and not the full content to show up on these single post views of your blog.