Sponsored radar – Radar picks up exceptional posts from the whole Tumblr community based on their originality and creativity. It is placed on the right side next to the Dashboard, and it typically earns 120 million daily impressions. Sponsored radar allows advertisers to place their posts there to have an opportunity to earn new followers, reblogs, and likes.
Webmasters and content providers began optimizing websites for search engines in the mid-1990s, as the first search engines were cataloging the early Web. Initially, all webmasters only needed to submit the address of a page, or URL, to the various engines which would send a "spider" to "crawl" that page, extract links to other pages from it, and return information found on the page to be indexed. The process involves a search engine spider downloading a page and storing it on the search engine's own server. A second program, known as an indexer, extracts information about the page, such as the words it contains, where they are located, and any weight for specific words, as well as all links the page contains. All of this information is then placed into a scheduler for crawling at a later date.