You can easily recognize a Drupal site if its URL is smth like node/89, node/167. Drupal uses "nodes" to identify pages by their position in your database. For example, this page called "URL aliases" is actually known as "node/447" to Drupal.

Technically, there is nothing wrong with it. But it looks unreadable for human.

Drupal has a feature called "URL Alias" that allows you to provide a more understandable name to the content. As far as browsers, servers, and search engines go, it is totally unnecessary. But for humans, it is nearly mandatory. This is why most consultants tell people to always turn on the Path core module, which supports URL aliasing.

You can administer the URL Aliases directly on the node edit or add forms, or by doing the following: go to: Admin > Structure > URL Aliases.

Master Drupal in 7 hours - Configure SEO - Configure Path auto

Add custom Alias

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Existing system path:  Specify the existing path you wish to alias. For example: node/28, forum/1, taxonomy/term/1+2.

Path alias:  Specify an alternative path by which this data can be accessed. For example, type "about" when writing an about page. Use a relative path and don't add a trailing slash or the URL alias won't work.

Automated alias settings

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These should be set based on how you want your urls to look like on your site. If you want all blog posts to start with "blogs" and include the user id and title, you could use: blogs/[user-raw]/[title-raw].

If you create a special content type and what that to be part of the url, you can do that as well, e.g.   [type]/[title-raw]

Simply look at the "replacement patterns" and decide what pieces you want to use in your URLs for different content types. You can create your own replacement patterns using tokens.

It is good idea to try to think through your Drupal pathauto URL aliases settings before creating a bunch of content so you don't have to worry about the aliases changing due to changing your rules and patterns.