Author: Patrick

If Excel, Powerpoint, and Outlook operate the surface level, what you can see of modern business, COBOL is the collective history of plumbing keeping a business functioning. Especially when it comes to financials.

Consider: Over 80% of in-person transactions at U.S. financial institutions use COBOL. Fully 95% of the time you swipe your bank card, there’s COBOL running somewhere in the background. The Bank of New York Mellon in 2012 found it had 112,500 individual COBOL programs, constituting almost 350 million lines; that is probably typical for most big financial institutions. When your boss hands you your paycheck, odds are it was calculated using COBOL. If you invest, your stock trades run on it too. So does health care: Insurance companies in the U.S. use “adjudication engines’” — software that figures out what a doctor or drug company will get paid for a service — which were written in COBOL. Wonder why, when you’re shopping at a retailer you will see a clerk typing into an old-style terminal, with green text on a black background? It’s because the inventory system is using COBOL. Or why you see airline booking agents use that same black screen with green type to change your flight? “Oh, that’s COBOL — that’s definitely COBOL,” laughs Craig Bailey, a senior engineer at Faircom, a firm that makes software to help firms manage those old systems.

And DOGE is just going to waltz in and retire these systems? Whoo-boy.