What is the difference between endoscopy and colonoscopy?

Endoscopy means looking inside the gastro-intestinal system with a light and camera. It has come to mean the stomach and upper intestines in common usage Colonoscopy is more specific in that it specifies which area- the colon

Endoscopy usually refers to the upper gastrointestinal tract, usually to the duodenum entrance, while colonoscopy is meant to investigate large bowel pathology.

Endoscopy is a generic term for examination of internal organs through a tube with a camera. Colonoscopy is endoscopy of colon.