Drupal SEO is pretty good out of the box. Adding things more to your site will be an advantage to more readable for search engines. Moreover, you should know about some SEO modules, custom Drupal Development to enhance your site.
Here we are listing some modules
The Pathauto module automatically creates URL/path aliases(human-friendly URLs) for various kinds of content (nodes, taxonomy terms, users) without requiring the user to manually specify the path alias. This allows you to have URL aliases like /category/my-node-title-string instead of/node/123. The aliases are based upon a “pattern” system that uses tokens which the administrator can change.
The XML sitemap module creates a sitemap that conforms to the sitemaps.org specification. This helps search engines to more intelligently crawl a website and keep their results up to date. The sitemap created by the module can be automatically submitted to Ask, Google, Bing (formerly Windows Live Search), and Yahoo! search engines. The module also comes with several submodules that can add sitemap links for content, menu items, taxonomy terms, and user profiles.
GlobalRedirect is a drupal module helping out to face some drupal problems
Once enabled, an alias provides a nice clean URL for a path on a site. However Drupal does not remove the old path (eg node/1234). The problem is that you now have two URLs representing the same content. This is dangerous territory for duplicate pages which can get you sandboxed by the search engines!
This project allows you to add meta tags to Drupal pages, both manually and automatically based on various settings. Paying attention to meta tags, such as keywords, description and canonical URL, may help obtain better search engine positioning. The module aims to support the most useful meta tags, others may be created using the module’s custom hooks.