White sugar is sugar that has been refined and washed so that it has a white appearance and no molasses flavor. The flavor is relatively neutral, making it a popular choice for baking and sweetening drinks. Most markets sell white sugar, often in several different forms, and when recipes call for sugar, they usually mean this type of sugar, unless the recipe explicitly calls for another variety.
Sugar comes from either sugar cane or sugar beets. In both cases, the plants are crushed to exude their sweet juices, and the juice is allowed to crystallize into a loose crumble. This crumble can be sold as-is, but it is usually washed, allowed to crystallize, and then sold or refined as needed. In the case of white sugar, multiple washings are used, with some refineries even bleaching their sugar to get it as white as possible. After the sugar has been sufficiently refined, it can be allowed to dry before it is packaged.
Granulated sugar is the most readily available form of white sugar. It comes in a range of grades, including nib sugar, table sugar, and caster sugar. The sugar can also be finely ground to make confectioner's sugar, which is often blended with a small amount of cornstarch to keep it from clumping together. Producers can also mold it into sugar cubes, which are often used to sweeten drinks.
This type of sugar is the most processed form, but some people prefer less refined varieties or sugar alternatives, such as sweeteners made from agave nectar or honey. Many refineries that make white sugar also produce brown sugar, which has been blended with molasses. Light and dark forms of brown sugar are available. This type of sugar tends to be more sticky and clumpy because of the increased moisture, and it also has a very distinctive flavor that makes it unsuitable for some applications.
In contrast with heavily refined white sugar, some companies also sell “raw” or “minimally processed” sugar that has not been as heavily washed and bleached. This sugar has a light golden color due to the remaining molasses, and a flavor that is somewhere between brown and white. Some people view minimally processed sugar as a more natural and healthy product, especially if it is organically produced.