Strange permission requests

[Nesaskewatch]

For the past couple of days I have been getting requests for my password for no apparent reason. It will simply pop-up and ask at random times. In fact, it just did it while typing this. When it first happened I thought it must be normal and entered my password, but since have been cancelling unless I am doing something that obviously needs permission. How can I find out what is making these password requests?

Thanks for any help.

[Nesaskewatch]

OK. In my panic I overlooked the sticky(s). I will review and try to find out what is going on before posting in here again. I did install a ppa from someone I do not know which really has me worried, but I am likely over-reacting to something normal. Right, I'm off to the salt mines!