Preview of images

When I upload Jpeg its nice that I get to see previews. But if I click on them, I need to see them "In big" again, as in full-scrreen or sth. Because sometimes I upload something and I need to look at it again myself, but I dont want to leave navar again and have to find the screenshot in its source data storage or whatever, but quickly click here, and have a glance again on what it says.