I think today it has been made easy due to availbilty of internet sources but it was very difficult in the near past. Moreover, It was very very difficult in very far past

Thanks dear @Atiqe Ur Rahman for your valuable response.

One of the main differences is that research is nowadays done mainly using computers.

Muhammad,

This is an interesting question that will depend in part on what field you are talking about. On the most basic level, in the past, scholars did not have to "publish or perish," so arguably there were fewer articles published and fewer "superstars" since the most published scholars might have had only a dozen articles and we had no communication "network" aside from yearly conferences with which to interact. There were "famous scholars," but when I was in graduate school, it was a very different standard than it is now, and twenty or fifty years before that was also different. The professors at Purdue (we had three at the time who were on the most published scholars in communication lists) were known for only a few articles and if they published more than an article a year or a book we were impressed.

Another interesting point is that a great deal of the most important scholarship and thought was in books. In all my classes as an undergraduate and through several of my years in graduate school, we used books and course packets. That is still true in many fields but not all. Now, the coin of the real is the journal. In the US, there was also a shift from copy packets of chapters and articles to textbooks, mostly because of the Kinko's lawsuit in the 80s (1989, settled in 1991) which made it more difficult to use books and article without paying for them. There are other factors, but we saw a shift in the late 80s–early 90s in terms of what we use pedagogically.

A third issue, mentioned by Atiqe above, was the internet. I wrote a couple of articles about Google Scholar when it first came out, and I still believe it was the most important research innovation probably ever. Google Scholar, and now sites like ResearchGate give scholars and students access to research that was never available in the past, and access to leaders in their fields who could never have been reached in the past.

A final point, because I have work to do now and could go on for hours, is that, as noted above, the bar has risen on what is expected from scholars in terms of scholarly productivity. When I was looking for my fist job in 1997, an applicant who had half a dozen conference papers and one article was sufficiently competitive. Now, we send our PhD students out with a dozen conference papers and three to five articles. The "average" (or typical) scholar in communication published one or fewer articles his/her whole career. Now that bar has risen considerably and our graduating doctoral students can now publish 2–3 articles per year, and "top scholars" publish three to five or more.

Thanks for your valuable reply dear @Nidhal Kamel Taha El-Omari

Thanks dear @Michael L. Kent for participation in discussion. The answer covers almost the all aspects.

Agree with Michael L. Kent

Modern technology in data analysis and presentation, use of neural networks, electronic control, and the abundance of information on communication sites are the most important differences that make the speed of achievement exceed expectations

I think that in the past, research was more difficult and required a lot of effort to get to the information, while at the present time it has become much easier with the availability of modern sources of information such as computers and the Internet

(But, I think that the more difficult it is to obtain information, the more difficult it is to forget it)