There are now a very large number of search engines. Submitting a site for indexing to all of them is a time-consuming and tedious process. Multiple site submission is the process of submitting a Web site to a number of sites for indexing by accessing only a single Web page. Such a Web page is maintained by companies who offer multiple submission services. They often charge for this service, but there are a number of free services available. Sometimes payment involves accepting a banner advert on the site. See also all in one search engine.