What is the difference between "whole wheat bread" and "light whole wheat bread"?

I have read that "light" refers to the yeast that is added to make it "lighter", so it doesn't refer to the colour of the bread. Does it mean that "whole wheat bread" contains no yeast?

Thank you in advance.
My automatic bread machine didn't come with a recipe for that, so I really have no idea. I wouldn't want to eat whole wheat bread that has no yeast, however.
Where did you read that explanation, Antonija? And what is it that you're translating that contains the phrase "light whole wheat bread"? Context might be important here. My guess would be that (in a modern context, at least) "light" whole wheat bread has fewer calories than "regular" whole wheat bread. Or, it's possible that the texture is somewhat lighter. However, regular whole wheat bread definitely needs yeast.
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Actually, the context is The South Beach Diet Cookbook, so it could be what you are suggesting, khoff.
I found this explanation on the Internet,in various on-line dicztionaries.
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Whole wheat bread : 'bread made with whole wheat flour.'

Light whole wheat bread : 'bread with less calories, fat or cholesterol.'

Thank you.
Thank you all, Philip, khoff and Toms.