Many of us (I won't be wrong if I say all of us) use Google every day to search content on the Web. To cut a long story short, the text that we provide in the textbox on Google's page is used to search the pages on the Web that it has indexed. The search results are then returned to us in an order determined by Google's page rank algorithm. We might want to have a similar functionality in our database that lets us search for some text content and gives the corresponding search results. Note that this text search is not the same as finding the text as part of a sentence, which can easily be done using regex. It goes way beyond that and can be used to get results that contain the same, are similar sounding, or have a similar base word; we can even return even a synonym in the actual sentence.

Since MongoDB Version 2.4, the text indexes introduced let us create text indexes on a particular field in the document and enable text search on those words...