By educational standards, .edu is the most reliable source, followed by .org, and a close third of .com. However, this is not always the case, for organizations (.org) such as Wikipedia is not mainly trusted. Also, you must note that just because it has .edu does not mean it should be trusted either, for it may be biased to a certain thought.
Their is pertaining to people. Example sentence: Their books fell. And there pertains to a place. Example sentence: We are going there. Hope this helps.
