Indexing is the organization of information that occurs after crawling which allows pages to be seen on search engines. However, your page must be able to be crawled before indexing can occur. Therefore, it is important to have all your website pages available for crawling.
When searching at the most basic level, Google's algorithms will analyze your search terms in the index to find appropriate pages for you. If you are looking for 'computers', it is likely that you are also searching for pictures, videos, a list of different brands, etc. Google's indexing systems will note many different aspects of pages such as videos, pictures, and when they were published to provide potential visitors to your site valuable content.
By having more control over your domain authority, the more likely search engines will be able to crawl and index your website.
There are two definitive ways to ensure that an important page or set of pages is included in Google's main indices:
For more information on how you can help Google to crawl the right content on your website, please visit https://support.google.com/webmasters/answer/6065812?hl=en