What do the little stars on professional digital thumbnails mean?

Question

Not a photographer myself, so not sure how to describe this - but I'm looking at a page of thumbnail photos (taken on a digital SLR) and they have various little signs in the corner of each photo. In the bottom right hand corner there is something that looks like a soda stream (!) and sometimes another little square with a line in it. In the bottom left hand corner there are stars - either one, two or three. Does anyone know what the stars could mean?!

Answer 1

the definition of the pics:

* 320 x 240
** 800 x 600
*** 1024 x 768

values might be different, but there's the idea

Answer 2

Another example is squares or rectangles. I will normaly have one but They will be stacked 1,2,3 etc this shows my setting up how many pictures per second.

I have a sun for a white balance indicator. One feature with a star is an auto setting of your setting ie outside cloudy,outside bright,etc