Slugs are URL friendly versions of Post, Page, Category, and Tag names.
How Slugs Work
When you give a Post, Page, Category, or Tag a title, WordPress will generate a slug automatically.
The slug is the portion of the URL that refers to that specific page. Generally speaking, slugs tend to be very similar to the original title.
A slug will be different when the title contains certain characters, like spaces or currency symbols, as well as anything else that isn’t a letter or a number.
In those cases, the special character is either replaced with it’s URL friendly equivalent, or left out of the slug entirely.
The most common substitution is in titles that have more than one word, separated by spaces. In that case, each space is replaced by a hyphen ( – ).
Posts & Pages
You can view the slug for a Post or Page by visiting My Site(s) and clicking either Blog Posts or Pages on the left menu.
Next, Edit from the dropdown next to the item that you’d like to find the slug for:
On the Edit Screen, the slug will be located under More Options in the left menu:
You can also use this section to edit the slug if you’d like to use something other than the default.
Categories & Tags
The instructions from this section of the guide are referring to the WP Admin dashboard. You can get to this dashboard by adding /wp-admin to the end of your site’s url (e.g.: example.wordpress.com/wp-admin)
If you’d like to find the slug for a category or tag, visit Posts -> Categories or Posts -> Tags in the Dashboard.
Once you’ve loaded the Category or Tag page, you’ll see a listing on the right of all your current items. The Slug column will display the slug for each category.
Numbers At The End Of Slugs
Sometimes, you may find a slug has a number at the end of it that you didn’t put there.
This happens when WordPress detects the same slug being used more than once.
Because the slug is the identifying part of each post, page, category or tag’s address, they have to be unique.
An example of when this might happen is if you wrote a post entitled “Happy New Year!” The default slug would be happy-new-year.
If you were to write a similar post with the same title the following year, the default slug would be happy-new-year-2 to ensure that the two posts had unique addresses.
If you’d like to change the slug to something unique, rather than have the number added, you can edit the post and identify the current slug, and modify it right there!