Submitting your pages to search engine for getting indexed in the search engine database is called as search engine submission. The leading search engine like Google, yahoo, and MSN use crawler to find pages for their algorithmic search result pages. pages that are link to other search engines do not need to submit because they are found automatically.
A purpose behind making website making website is to bring traffic and to make conversion suppose some one make website and put it on the internet. But there is very less possibility to be seen on the internet by user.
If you want your site should be seen on search engine result page, the search engine crawler must crawl your site pages and indexed in to the database until and unless it won’t be crawled there is no possibilities of having site on the internet.But how crawler will come to know about that unless they get path to crawl your site just for getting them known search engine provides add URL page that let you submit your site to the specific search engine. There is a possibility that google will crawl and indexed your home page only .that’s why it make sence to submit one or two other pages from inside your website via add url page This is the primery stage to make people aware about your presence on the internet.