Search Question

These are probably an easy questions, but I can't find the answer in any of the documentation:

What is the difference in the search window when a file name shows up in red versus black?

What does the speed indicate when it shows up in blue instead of black?

And finally, what is the difference when the status shows a plus sign (+Available) in front of "Available" versus just the word?

Is there a good FAQ available? What was on the web page is greatly lacking...