First of all thank you for your quick and informative reply. I honestly never thought I will get response this quickly. :)
well, I did not use timer when I wrote this essay. however, I strongly believe it took more than 30 minutes. I guess, it took 35-45 minutes to write the draft and another 5-10 minutes for revision and editing purpose. So, as you said, time management is the main barrier for me right now and I am working on it. Nevertheless, I read my essay again and found that some sentences are not that important here. For example, from 1st body paragraph
With the help of internet, we can learn about anything through few mouse clicks of our computer.
I searched again in Google to find Youtube links and it gave me the exact link of learning java from Youtube.
and from 2nd body para
As science and technology advances, we are getting more and more advance devices and features.
are not that much important. If I delete those i think it will not hurt my essay. However, my strategy is, write perfectly what I think while I am writing. And after writing generally I make require modifications. I believe most of us write and modify in this fashion. But for toefl, I think I have to change my strategy otherwise time management will remain just a dream. :(
By the way, my exam is next month and I have plan to write one essay everyday. So I hope I can reduce time gradually. Moreover, I also hope that you guys will check my writing, at the same time help me to identify my mistakes so that I can improve further.
Thanks once again to both of you.