What Are Permalinks?
A permalink is the URL or web address of a WordPress page or post. Whenever someone wants to share a page from your site, that person will use the permalink of that page. As the term implies, a permalink should be permanent. If you change the permalink of a post or page, you may lose existing inbound links to it.
Permalinks can improve search engine rankings if you know how to optimize them. Search engines weigh many factors to deliver the most relevant results to their users; one of these factors is URL structure. If your web page URLs contain your targeted keywords, those pages may rank higher in search results.