The epidemic of diabetes and its complications are a major health problem that faces modern society. According to the data provided by the International Federation of Diabetes (IDF), one in every 11 adults aged between 20 and 79 years old was diagnosed with diabetes mellitus in 2015. Diabetes is a global problem; therefore, cheap, fast, and effective screening methods are needed to prevent diabetes complications such as cardiovascular disease, diabetic kidney disease, diabetic retinopathy, and neuropathy. Noninvasive diagnostics methods are more than welcome. However, prior to engineering work, one needs to become familiar with diabetes in general. Therefore, a brief introduction to diabetes is presented in this chapter, including past, present, and future achievements in this field.
