A recent reference question led me on an interesting journey discovering more about online family trees. Using a family tree service on the Web has attractive benefits: a centralized location on the Internet to store your family information, the immediacy of sharing by digital means your information with relatives and potential relatives, the thrill of locating new individuals or information to enhance your tree and further your research, not to mention networking opportunities to really thrash out a stubborn brick wall.
While it is quite easy to sign up and start adding information to these family tree services, questions about the reliability of the information in any tree will certainly arise for many family historians. Assessing the quality of data represents the beginning of the process. It is through verifying and reviewing the original work referred to in the citation that a researcher can determine the true quality of the source and its citation, and thereby the family tree. Unfortunately, many online family trees are unsourced, and should be considered clues, not facts, until validated with documentary evidence from several sources.
After reviewing terms of service statements on several family tree sites, a lingering question I have is what happens to your data when you no longer want to use the service. Only one company, MyHeritage, has a discussion within its privacy statement about deleting a section of a tree, the whole tree, or the entire account. Other companies are premised on the concept of building a single global tree, and so the expectation is that your data remains after you part ways with the company. If I have missed something in reviewing these statements, I would be interested in constructively expanding my knowledge and post a follow-up.