One point to keep in mind is that different yeasts handle different sugars differently.
For example, wine yeasts are better with fruit sugars but deal less well with malt sugars, while beer yeasts may struggle with fruit sugars but just love malt sugars.
In the context of "brewing sugars", we generally look at sucrose (a.k.a table sugar, which is a di-saccharide) vs. dextrose (a.k.a. corn sugar) or glucose. The latter are both mono-saccharides or simple sugars which the yeast absorbs and metabolizes directly. Most beer yeasts, by and large, handle dextrose better than most wine yeasts do, while both just love glucose.
Yeast cannot directly absorb an metabolize di-saccharides such as sucrose. Before yeast can ferment sucrose it has to break down that sucrose into a mixture of glucose and fructose. This mixture is known as invert sugar, and you can invert sucrose yourself prior to fermentation by boiling it in water with a little citric acid. See Google for details.
Most wine yeasts handle sucrose well without producing any off flavors. Most beer yeasts, on the other hand, don't really like sucrose and may produce a cider-like flavor and an aroma reminiscent of green apple or freshly stripped tree bark (due to a substance called acetaldehyde being produced in fermentation) in the presence of high levels of sucrose.
But there are exceptions. Belgian ale yeasts, for example, handle sucrose a lot better than other beer yeasts do, due to the fact that Belgian strains often have a certain amount of wine yeast in their ancestry. Belgian strong ales are traditionally brewed with a certain amount of sucrose in order to improve wort fermentability. Note that clear Belgian candi sugar is plain old sucrose, while the brown candi has been (partially, mostly or entirely) inverted and somewhat caramelized.