Thanks CandidateX for this essay. I’ve analyzed it quickly with two of the Readability tools at the top of this page (under the heading “Useful Links”).

Your essay is 460 words long. This is much too long for IELTS. You are only required to write 250 words.

There is no penalty for writing more, but candidates who go over 330 or 350 words almost always penalize themselves by making more mistakes, by not planning properly, by having too many unnecessary words and ideas, and by not fulfilling the task, which is designed to be accomplished in 250-300 words.

So the first step I would recommend towards a higher band is to write much shorter essays.

The second statistic is that your average sentence length is 18.4 words. This needs to fall dramatically to about 12-15 words per sentence. Here are some ways to do this:

• Write a few shorter sentences, especially topic sentences. Short means 4-10 words.
• Break up long sentences into two or three shorter sentences.
• Have only one idea per sentence
• Avoid long dependent clauses
• It’s an opinion essay, not a history or a research paper. Give your opinion in short, clear terms, and don’t give unnecessary background, particularly if this is obvious already.
• Use shorter vocabulary. Over 18%of your words are complex (long, multi-syllable words).
• Avoid the passive. Make sentences active
• Remove all unnecessary vocabulary and phrases
• Make sure every sentence is relevant to this topic.

Introduction

In your 77 word intro (yes, it’s far too long) you wrote:

In 21^st century a lot of things have changed dramatically. Technology has improved to such a large extent that it is rendered our lives to become more convineint and comfortable. Mass media such as radio, television and internet are also one such invention which has influenced human kind immensely. Nowadays, it is observed that radio is becoming less popular when compared to television and internet and this view point is supported. This is analyzed with examples below.

Let’s check the topic again. The topic is radio. But in your intro, two entire sentences (you should have about 20 sentences) are talking about something else -  comfort, convenience. Are we discussing armchairs or fast food, or laser eye surgery?

Yes, perhaps it’s sort of related, technology, yada yada yada. But it’s not the topic. You need to get to the point immediately if you only have 250-300 words.

The last sentence is generic. You could use it in a million essays. Get rid of it, or make it specific

Remove the passive “it is observed”  and the passive “this viewpoint is supported.”  It’s an opinion essay, not a scientific paper. Where is your opinion?

Check for basic errors in agreement and for logic in ideas. How can radio, the television and the internet be one invention?

Here’s a possible rewrite based on your ideas. I’ve added a thesis sentence (a sentence that tells the reader what you are going to do and/or gives your opinon).

Radio is becoming less popular compared to television and internet.  In this essay, I will explain why I think radio will continue to decline.

Paragraph 2

Paragraph 2 is about the history of radio and why it was popular, but there is a very long (24-word) sentence there about television. Paragraph 3 is about television, so what is this television sentence doing here? Is this paragraph really about radio? We don’t know, because there isn’t a nice short topic sentence at the beginning.

You wrote: 

Until  television became available to common man, radio was the most famous mass media of communication for entertainment and news. However, when television started becoming affordable it started attracting more and more people since television could connect to people with both audio and video. Today raidio is used less, it is mostly used to listen news, sports commentary or songs while driving or when one is in a remote place without access to television or internet. 

Let’s focus this paragraph with a topic sentence that tells the reader what this paragraph will be about -  radio.

Radio has some advantages. It’s good for catching up with the news when you are driving or in a remote area. You can listen to music or follow a game while doing something else. It’s not too distracting, it’s free, and it’s available almost everywhere.

Paragraph 3

Your paragraph three is about television. Fine! But do we need 145 words on television? We all know what it is, and the topic is radio, radio, radio, and radio’s inevitable decline.

You wrote:

One of the most important advantage of televion is being able to watch motion pictures while listening. Other advantages include being able to watch programs of interest. News on television can better affect, provoke and inspire people to react to the situation. For example, tragic event of tsunami in Japan was viewed by many people across the world and people shared their sympathies and offered help to people of Japan. This could not have been achieved so effectively via medium of radio. When entertainment is considered television offers various variety of programs  for different age groups and is considered one o f the interesting medium of pass time. Sports events can be watched live with all actions. Thus, it can be seen that television offers a lot of convenience and comfort of being able to watch programs telecasted at far of countries sitting at home.

(145 words, 18.1 words per sentence, 62% passives) 

Let’s change the focus and keep some of the ideas in a much shorter form. Let’s start with a short topic sentence which outlines the paragraph:

But television is far more engaging and interesting than radio. The images and sounds of televised news demand our attention in a way that radio cannot. For example, footage of Japan's tsunami shocked the world, but also inspired people to react and help. Television is also much more entertaining than radio. Films, soap operas, quizzes, game shows, documentaries and sports are just some of the range of programs available in the comfort of our homes.  

(76 words, 5 sentences, 15 word average sentence length, topic sentence, two ideas  -  three would be better -  and supporting information for each one).

Paragraph 4

This paragraph is about the internet. Fine! But remember the essay topic is radio. Compare, contrast, point out the differences, relate all ideas to the topic. Repeat the topic endlessly in your head and make sure every sentence is about the topic.

You wrote: 

Internet is another great invention which hols a ocean of information and can also be very interactive. Through internet once can access news or any entertaining program like movies or songs at the click of a button from anywhere. This medium of internet is also widely used in education since it has the encyclopedia of information. It favors the social media such as facebook , twitter and emails which is most successful medium of communication in present days. The recent political event in Egypt was triggered by Facebook which spread like wild fire. This shows the strength of internet in connecting with people.Through internet once can also learn about new places and take a virtual tour via google earth.  This shows the advantages of Internet over radio.  
126 words, 18 words per sentence, 14% passives.

Let’s put your final sentence from this paragraph at the start as a topic sentence:

However, the internet is an even bigger threat to radio than television. First of all, it’s personal. It allows us to access our choice of news, information and entertainment, whereas radio and television broadcasts are the same for everyone.  Unlike radio, the internet is interactive and social, with applications such as Twitter, Facebook and email. Because of this, the internet also allows us to act together. Recent events in Egypt and the Middle East spread through the internet, rather than old media such as radio or television.   

87 words, 6 sentences, 14.5 words per sentence, no passives. 

Conclusion

Your conclusion is 35 words long in one sentence. That's much too long. There are serious grammar errors and too much repetition of the question prompt.

A conclusion in IELTS should  summarize both sides of your essay, give your opinion and look to the future. And do it in several short sentences.

You wrote:

To sum up, when clearly analyzed the advantages of Television and internet over radio, it becomes evidently clear that radio will no longer be able to hold its presence  as  a mass media of communication

Here’s a possible rewrite:

To sum up, radio is not as interesting or immediate as television, and not as personal and social as the Internet.  I cannot see much of a future for traditional radio stations. Unless they evolve or move to a more Internet-based form, I think radio’s days are numbered.

Overall, you need to write much less, and go through your writing and ideas with a scalpel to remove all the unnecessary words, phrases and ideas. Stick to the topic. Don’t stray. Use short topic sentences at the start of every paragraph. Read and re-read the question. Make every sentence relevant to the topic. Avoid empty phrases and clichés. Your essays will be shorter and simpler, but much more effective.