Sometimes it’s hard to know the difference because they appear so similar: i.e. dark and round. Freckles are small, dark spots that appear on the skin due to sun exposure. They’re usually harmless and don’t require any special care (aside from SPF to avoid darkening). Moles are also small, dark spots that can appear anywhere on the skin. However, moles can be either benign (non-cancerous) or malignant (cancerous). If you have a mole that’s changing in size, shape, or color, see your doctor to have it checked out.