The term metadata refers to “data about data” (e.g. card catalog at the library contains metadata – the Name of the Book, subject, where to find the book in the library, when it was written and information about its contents)By Albert N. Milliron
I can give you another example of what we do here in the office. We have something called a Software Defined Radio (SDR) that has the ability to record large chunks of the radio spectrum including satellite TV. If we get an indication that something is happening that we would like to review the radio traffic or a specific satellite Television station, we simply go to our hard drive time stamp and review the radio or TV traffic for that time frame.
Now, if nothing happens (like Breaking News) we simply allow that part of the hard drive be overwritten. We can literally go back in time and review police, fire, emergency traffic on our radios to get full information on a story we are working on.
Now we are not the Government, we have a small company here with limited resources. Still, we are able to record on a daily basis Radio and TV traffic and go back and get them if needed. The government has large facilities with billions of dollars of equipment and personnel. They also have large storage capacity.
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