Protein bars are snacks that contain a higher share of protein than classic sweets, usually through the addition of protein sources such as whey, milk protein or soy protein. These are processed with binders, sweeteners and sometimes nuts or dried fruit into a firm mass.
In practice, the actual protein content varies greatly between products, so a look at the nutrition table makes more sense than relying on the name alone. Protein bars also often contain sugar alcohols or other sweeteners, more on this in the entry Sweeteners in powder. They can be practical as an occasional snack on the go, but they do not replace a complete meal.
What to look out for in the list of ingredients in general is explained in the entry Ingredients list, and the Protein bar guide offers a comparison of different bars.
