["firmly packed light brown sugar"]

Hi everyone!
I just got two of the Magnolia Bakery cookbooks (  ) and while reading the recipes, I stumbled upon "firmly packed light brown sugar" and I have no idea what it is. I have never heard of a sugar type like that. 
Could someone tell me what it is, please??

hi y'all 
I've been browsing this forum for quite a while now and all your craftiness (if this is a word...) made me wanna be/do the same *g*.

It finally went so far that I got my own sewing machine and I made a skirt (woohoo).

Can't wait for the patchwork workshop that I'm going to attend next month.

I just hope to have a good time here on craftster, so, uhm, happy crafting