The default permalink structure for WordPress is completely date-based. This means that every link to your posts has a combination of the month and year in the browser link.
If you look in the Permalink settings section of the WordPress settings, you will see it set similar to the following:

Default WordPress Permalink Structure
As you can see, it’s set up to use the year, month, and post slug for the permalink. If you were to write a post in this configuration, the resulting link would look similar to this:
http://wpelevate.io/2018/09/announcing-elevate-1-0-for-wordpress/
It certainly is functional, but it’s not very good from a SEO perspective as the date doesn’t really contain anything useful in terms of information, and it even serves as a reminder of how old your content is when visited in the future.
We typically recommend people switch their permalink structure to one that is category based, which removes the date information from the link and allows a site owner to insert additional keywords via the category. We usually set ours to a custom structure that is set to /%category%/%postname%/.

Setting a Custom Permalink Structure in WordPress
This will instruct WordPress to also include the primary category slug as part of the permalink, and let’s you have the ability to include more keywords in the permalinks by creatively assigning posts to categories.
Now, let’s say the exact same post was assigned to the category “Plugin Releases”, which has a category slug of “plugin-releases”. When WordPress constructs the permalink in this configuration, it will include all of the information from the category and the post. This results in the following permalink:
http://wpelevate.io/plugin-releases/announcing-elevate-1-0-for-wordpress/
Which now has “plugin-releases” as part of the link. So in terms of keywords, we’ve now introduced two more – one indicating it’s a plugin, and another that it’s a new release. These are subtle changes, but they do help with SEO and give site authors another creative way to influence how posts are ranked.
Once this is done, make sure you also install and use a WordPress SEO plugin such as Elevate for WordPress.