Spectacles or Glasses are typically used for vision correction, such as with reading glasses and glasses used for nearsightedness.
spectacles, are devices consisting of glass or hard plastic lenses mounted in a frame that holds them in front of a person's eyes, typically using a bridge over the nose and arms which rest over the ears.
Sunglasses allow better vision in bright daylight, and may protect one's eyes against damage from high levels of ultraviolet light.
Typical sunglasses are darkened for protection against bright light or glare; some specialized glasses are clear in dark or indoor conditions, but turn into sunglasses when in bright light. 
Most sunglasses do not have corrective power in the lenses; however, special prescription sunglasses can be ordered.
People are more likely to need glasses the older they get with 93% of people between the age of 65-75 wearing corrective lenses