The word "research" as in "genealogical research" is often used so broadly as to almost have no meaning. I am going to discuss the topic and put the concept of research into a little better focus. In a more narrow and practical sense, research involves searching for information or data that is presently unknown to you. You might use the term research for looking up the price of a store item online. You say, the price is the unknown, my search online is research. In the genealogical context, I don't know my great-grandfather's name, I search online and find his name, that is research. I would disagree and would like to bring he concept of research a little further from simply looking up information you suspect is already there. You probably would not go looking online for the price of a computer if you didn't already know that the stores listed their prices online. Looking for your great-grandfather's name is not exactly the same as looking for a price online, but it can be about the same. What if your grandparents are still alive? Is looking for your great-grandfather's name online still research?
If you were going to do research for a Ph.D degree, you would have to demonstrate that what you were researching had not already been done before. I am not advocating that doing genealogy is like getting an advanced university degree, but I think the term "research" should at least be limited to apply to those situations where you are discovering information that was not easily obtainable or generally known.
Before you can do "research" you have to know what is already known and have a good idea of what is not known. When I use the term, I understand research to pertain only to the unknown, not the known. Finding out what is known is part of the research process but it is not research. In genealogy we talk about doing a survey before beginning to do research. I find many genealogists are stuck in the survey stage of the genealogy process and have never made it to doing research. What is tragic is that they don't know they haven't made it out of the survey process and think they are doing research.
I don't want to minimize the difficulty of the survey step in the research process. It is not easy to find out what has been done. Before computers, I spent more than ten years off and on in the Salt Lake Family History Library before I had a reasonable idea of what work had been done on my family and before I could even start to do what I considered to be research. As they say, your results might be different. You might run out to the end zone of the survey step in a very short time. On the other hand, you may wrongly THINK you have finished the survey and not have the slightest clue as to the extent of the genealogical research done on your family.
Upon reflection, completing an adequate survey of the information readily available on your family could even be harder than it was years ago because of the proliferation of places to look. For an example, when I did my initial survey, I had no way to determine if there were any surname books available about my family. In fact, I was only vaguely aware that there might be more surname books than the two or three I had in my own library. Years into my initial survey, I found several other books about my family that I had no idea existed. I recently found a reference to another book that shows up in one library in Florida and is not available on Interlibrary loan. Unfortunately, the book is listed online at more than $100 and I am not sure that any of the booksellers actually have a copy or are just fishing for sales. But the fact that I know the book exists wouldn't have even been possible before the Internet.
The key to knowing when the survey step is over is contained in the phrase "reasonably exhaustive" which I borrow from the Genealogical Proof Standard. An exhaustive search will review every possible source tempered by the modifier "reasonable" that means you will not have to go to the ends of the earth, just to as many places as you can afford. How do I know what is reasonable? If your ancestors came from New England, the word "reasonable" would have an entirely different meaning than if they came from Eastern Europe in the last ten years.
How will I know when I am moving on from the survey stage to doing research? The easiest answer is when you stop finding information about your family in secondary sources and online family trees. I really do need to diverge here a little and point out that finding an online family tree that takes your family back generations without specific supporting source documentation is a trap. There is always the remote possibility that the information is accurate, but lack of source citations is a clear indication of lack of support for claimed relationships. I have posted about this problem before, but it bears repeating that absent source citations, there is not any way to substantiate or believe a user contributed family tree.
Back to the issue of coming to the end of a genealogical survey. Research is a process not a destination. At any moment you may find information about your family that puts you back in the survey stage. Too many researchers find a "new ancestor or ancestral line" and take off copying out the information without redoing the survey with the added information. Once you have made a connection with the new family line, you should immediately go back to looking for what might have already been documented about the new (to you) family members.
Let's start with the assumption that you know nothing at all about your family except your parents' names (and you might not know that much). Almost ever guide ever written about genealogy will tell you to start with your own records and those available from family members. I am not going to worry about the situation where you don't know either of your parents right now, your research may start immediately. In the first case, a reasonable search included asking relatives for names and identifying information. In our electronic age, a survey may also included doing a reasonably exhaustive search on the Internet. If you don't know where to start, start with any of the websites, including the FamilySearch Research Wiki, that give you instructions on where to look for your ancestors.
At some point, you are going to realize that you have looked at everything you have in your personal documents. When you are satisfied that you have looked in all of the places you
reasonably expect to find documents or source material, then you may be
ready to start the research phase of your search.You will know you are into the research phase when you stop finding information that is already available from some other member of your family.