Diagnosed with diverticulosis- what is the difference between this and diverticulitis?

See below: Diverticulosis is the finding of small out-pouches that bulge out from the wall of the colon or large intestine, usually in the left lower colon. Diverticulitis is a painful infection of these pouches, treated with antibiotics.

-osis vs. -itis: "-osis" means you have diverticuli (small pockets or outpouchings within the colon. "-itis" means the diverticuli are infected. Having -osis increases your risk of getting -itis, but doesn't guarantee that you'll get it.

Infection or not.: Diverticulosis is the presence of diverticuli, while diverticulitis is an infection of same (technically a micro perforation which leads to infection).