This allows the equivalent of indexing a chunk of your own hard drive with Google. It is an amorphous tool that can be configured and used in many ways to suit the user's particular data and habits--and must be so configured. Like any tool, learning how to make efficient use of it requires experimentation. If you can keep track in your head of what information is in what documents and what those documents are called and where they are filed, then you will have no use for the program, but to this user who is organizationally challenged, any single application has ever enabled him to find things so easily. Two concern about using a database of this sort is that it be maintained properly and that your data be easily extracted down the road, when your needs change or the program ceases to be maintained. With DEVONthink, data are easily extracted and the few bugs I've found have been fixed promptly and the developers have been assiduous about informing users off an occasional serious problem that other users have turned up, and posting updates. For the power and quality of this application, the price is absurdly low.