uploaded picts folder

Under the admin’s Miscellaneous Options is the checkbox to “Organize my uploads into month- and year-based folders”. How are the folders organized if this is not checked?

The docs at http://codex.ww.wp.xz.cn/Miscellaneous_Options_SubPanel#Uploading suggests that even if this box is checked, it relates to upload time, not photo time (as in if the photo was taken last week, but appears in Today’s folder).

Does unchecking that box simply make one big folder?