Search Engines Results Page Defined
The search engines rely on keywords entered by users to search for information on the web relevant to the query. A resultant page from a keyword query by a user is what is what is defined as Search Engines Results Page. The search engines usually return numerous web pages, including the titles, a short explanation that shows where the keyword appears and matches the content in a page.  A SERP may either stand for a single page of numerous resultant links from the keyword search or the set of all the links that are shown after a search query.

Cached Pages
To enhance its performance, some search engines hoard pages for frequent searches and show the display the cached pages contrary to the live pages. The search results are constantly updated to accommodate the new pages and even adjust the rankings of the pages in the search results. There are chances that you may get inaccurate or outdated search results because they are refreshing of the search results can take numerous days or weeks. This may make some new sites and web pages to be completely absent from the SERP even though they may contain the keywords.

Sponsored Listings
Commercial search engines generate revenue by allowing some SERPs to carry advertisements. These adverts are usually placed on the right-hand side of the page as a tiny confidential ad. However, most of these sponsored listings are usually placed directly above the main organic search results. By so doing, the sponsored sites usually attain an automatic high ranking but the unsponsored ones are usually placed below in a different fashion. Advertised website doesn’t have to contain the relevant information to be picked by the search engine spiders as they are paid for.

Result Varieties

Different types of search engines, like Google, Yahoo and Bing usually include varied types of listings in their Search Engine Result Pages. The varied types include contextual, organic and sponsored listing results. More so, the images, maps, videos (usually YouTube) are displayed so long as they contain the keyword that was searched. However, these results are differentiated from one another by the search engines like the images, news or even blog posts. This makes it easier for the user to go directly to the desired type and form. Website owners have enhanced their SERP templates and made them more appealing on the main search result page so that the user may be attracted to the content.
How SERPs are generated.
The search engines utilize the content that is contained on the page and reserve to metadata tags of a web page to come up with the content that is usually contained on the SERP. The HTML title tag is normally used as the title of the result and the most relevant information with the keyword integrated used for the description. Sometimes, the web page may be missing and hence the information about the page from dmoz can be used in place.
Tracking SERP
Webmasters need to track of the ranking of the specific keyword by the search engines to attain top rankings. Multiple keyword trackers for numerous websites have been developed to make it easy for webmasters to track their keywords. The higher the ranking of the website, the higher the ranking it attains in the search engine's results in pages.