Search engines provide Internet users with rapid browsing techniques in order to find specific information they are looking for. The efficiency of any search engine is reflected in the accuracy of the various outputted results as a response to certain search queries.

They could give an increased priority in certain situations or restrict results depending on the URLs of websites and the specific parameters you specify when the custom search engine is created or modified.

Google allows you to automatically create custom search engines with the help of a web-based interface. The custom search engine can be integrated in any website even by beginners because the necessary code is generated automatically. At any given moment, the default parameters can be changed both for search results selection criteria and the display options of the search system (search box, results and ads).

The search results can be presented (hosted) on a non-Google website using the iframe or overlay option, respectively with a two pages system (one page containing the search box and the other the search results) or with a one page system (the results are displayed in a modal window). If you choose the search results presentation to be performed through a Google hosted page, a visitor will most likely be determined to leave your website in most of the cases.

A custom Google search engine could also be created on the fly for a links directory or a blogroll. In this case, it is recommended to use the internal search engine of the links directory in order to gain time and maybe an increased speed of search results display.

Due to the extensive usage of various CMSs (content management systems) for website development, many CMSs have already integrated or have developed modules that allow you to include a Google custom search engine into an existing website only with a few mouse clicks.

The inclusion method of a Google CSE in any existing website must be selected based on its functionality (the API could also be used in order to enable advanced features). The practical utility of any Google CSE will definitely be determined by the number and type of users' search queries. The return of the visitors will demonstrate that the CSE attributes generates search results with the relevancy situated in the range of users' expected accuracy. In other words, the CSE settings must always be adapted based on users' actions.