What camera shoots before pressing shutter button

Keith Newton
I seem to recall hearing about a camera that records a loop of images from about 20 seconds before the button was pressed, but can't seem to find anything. What is the term to search with?

You've seen images of the bears in Alaska waiting at the top of a waterfall, with mouth open and salmon in air just before,,,,,,,,, chomp. I had assumed that they probably had a cable to the button, set for continuous shoot, and were able to hit the button just as the fish leaped, but if the camera already had 20 seconds before that, I think my reflexes would be quick enough. ha

I seem to recall there is a good number of formerly professional photogs here, so I figured you guys still keep up with the latest greatest, so I ask?

© 1998 - 2017 by Ellis Walentine. All rights reserved.
No parts of this web site may be reproduced in any form or by
any means without the written permission of the publisher.