What is meant by TRP Rating?

I am sure this question must have popped up in everybody's mind at some point or the other.

What is this TRP, we get to hear a lot whenever a sudden twist or a scripted drama happens on the sets of reality shows and serials nowadays. We say this is all done to increase the TRP. Even some programs have to go off air due to the fall in TRP.
(let me tell you, this post is inspired by Rakhi Sawant's latest reality show 'Rakhi ka Swayamvar')

What is TRP anyway?
TRP, the acronym for Television Rating Points. It is the criteria that indicates the popularity of a channel or a program or an advertisement.

Who does this computing job?
INTAM (Indian Television Audience Measurement) is the only electronic rating agency functioning in India.

How is it measured?
INTAM uses two methodologies.
First, the frequency monitoring, in which 'people meters' (an electronic gadget, about the size of a paperback book, is placed on each TV set in the sample home. Each meter is capable of accurately monitoring every second, 24 hours a day, 365 days a year, what is being viewed on each TV set and by whom) are used to record the data continuously.

It reads the frequencies of channels, which are later decoded into the name of the channels and the agency prepares a national data on the basis of its sample homes readings.

But there is a drawback in this technique. As you might have experienced, cable operators frequently change the frequencies of the different channels. It may be very misleading to read a channel according to a particular frequency even if the down linking frequency is same all over India.

Second technique which is more reliable and relatively new to India is 'picture matching technique. Here people meter continuously records a small portion of the picture (instead of frequency) that is being watched on that particular television set. Data collected from the sample homes is matched with the main data bank to interpret the channel name. And this way national rating is produced.

But Doordarshan has its own ratings system DART (Doordarshan Audience Ratings). DART is a diary based system of ratings. DD people distribute diaries in sample homes and the viewers are asked to note down each program as and when watched by family members. At the end of the week a person collects all the diaries and sends them to the head office, where popularity of programs is calculated.