I have seen reference to online trees. What would be the advantages and disadvantages of me publishing my family information online?
There are many advantages and disadvantages to publishing your family history online. Listed below are a few. Your decision to publish online will depend upon your willingness to balance risk with potential gains.
You have to think of what you will get out of publishing to an online family tree. So what is your objective?
I am a bit down on online trees, so bear with me a bit in this answer.
If your objective is to collaborate with known relatives on some sides of your tree, then that might be a good use of it and a valid reason. Then I would choose an online site that limits access to your tree to only approved people, Then you and your relatives can work on the tree together.
If your goal is to merge your tree to others and get others to help you fill in your blanks, then you will probably cause yourself more pain than good. Your tree will be corrupted by the masses as they merge the junk that is out there into your tree most often without any sources to verify their claims.
If your purpose is to find new relatives, then I don't suggest an online tree. I have attempted a few in the past, and the people who tend to find you are usually unrelated, or are so far off in the periphery of your family that you have very little to gain from them. There are other techniques you can use to find relatives that are better.
If you have a different purpose, please let me know in a comment. Maybe there is a good reason out there that I have missed.
Perhaps I would feel differently if I had spent the time and/or money that many on this site have in pursuit of my genealogical research, but I am personally of the opinion that research should be shared as broadly as possible. I see my research not as something that belongs to me, but that is part of a larger whole, and is most valuable when it is shared.
Some other advantages:
As you can tell, I believe that the advantages outweigh the disadvantages, and that as technology improves, the scale will tip further and further in that direction.