Do you keep a simple blog, where you don’t define specific categories for your posts but simply let them all be uncategorized and use tags instead? Do you, like me, feel that all the categorizing stuff comes in the way of your content and your blog? Do you feel that keeping only one category seems superflous, but WordPress just forces you to? Then this plugin might be for you!
This plugin is mostly cosmetic, as it doesn’t change or actually remove any categories, but hides any options to change them, so all posts are in fact put in the default category (usually “Uncategorized”). This currently includes the category section on the edit pages and the “Manage categories” section on the admin pages. Published posts will not mention categories, and the Category widget has been removed.
As it doesn’t actually remove the categories or modify any files, this plugin will not affect any other plugins’ usage of categories. This means “Uncategorized” will show up on statistic pages, etc.

No Categories

Simply disables the usage of categories in your WordPress blog.

Paolo T. (pixline)

swergroup

Category Pages & Posts Shortcodes offers helpful shortcodes to display a post or page content, or a list of posts. 
It also allow an exclusive relationship between a Category and a Page, in order to display the page content as “header” of category archives, with a simple php tag.
You can safely use shortcodes inside a post or a page, you can embed them in your templates or in your sidebar 
using the <a href="https://codex.wordpress.org/Function_Reference/do_shortcode" rel="nofollow ugc">do_shortcode</a> WordPress function, like that:
<pre><code><?php do_shortcode('[showsingle <options>"]'); ?>
</code></pre>
<ul>
<li><a href="http://dev.swergroup.com/pages-and-posts-shortcodes" rel="nofollow ugc">Documentation and usage examples</a></li>
<li><a href="https://wordpress.org/support/plugin/page2cat">Support Forum</a></li>
<li><a href="https://github.com/swergroup/category-pages-shortcodes" rel="nofollow ugc">GitHub repository</a></li>
<li><a href="https://travis-ci.org/swergroup/category-pages-shortcodes" rel="nofollow ugc">Build status on Travis CI</a></li>
</ul>
This plugin is published under GPL2 open source license by <a href="http://swergroup.com/sviluppo/siti-internet-torino/" rel="nofollow ugc">SWER Sviluppo siti internet Torino</a>. If you find it useful, please <a href="https://flattr.com/submit/auto?user_id=swergroup&url=https://wordpress.org/plugins/page2cat/&title=Page2Cat%20WP%20plugin" rel="nofollow ugc">Flattr this!</a>

Page2cat: Category, Pages & Posts Shortcodes

Useful shortcodes to display a post or page content or a list of posts. 100.000 downloads!

No Categories vs Page2cat: Category, Pages & Posts Shortcodes