A special search command for Google. A search for allintitle:blue mango would only return sites that have the word "blue mangot" in their title.
A special search command for Google . A search for allintitle:widget would only return sites that has the word "widget" in the title .
A search command on Google which is typed in before a keyword to only show web pages with the specific word in their title on the search results. (See Title).