Many people bear the shame of having dark underarms, knees or elbows, or dark skin patches on the neck. People who have the problem with dark underarms, usually cannot raise their hands regardless and tend to be careful all the time. The underarms may have gone dark because of some of errors including shaving or utilizing chemical hair uprooting creams and antiperspirants.
The skin around the elbows and knees is generally thicker and has a bigger number of folds than its encompassing skin. There are no sebaceous glands so this skin tends to be drier.
Usually, dark skin patches around the neck are the skin pigmentation issue known as acanthosis nigricans, maturing and exposed to sun.