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The Ancient, Strange Coding Language that 95% of ATMs Use

The video spotlights COBOL, the 1950s business‑oriented language that still underpins the majority of ATM and online banking operations. Despite its archaic syntax, roughly 95% of ATM transactions and 80% of in‑person credit‑card payments run on COBOL code, handling an estimated $3 trillion in daily transactions. Key data points include the DoD’s 1960s mandate that every defense‑contracted computer ship with a COBOL compiler, cementing its ubiquity across government and financial institutions. Legacy systems now contain between 220 billion and 800 billion lines of COBOL, many of which were written before modern language features were added, making them difficult to modernize. The presenter likens COBOL to a “vampire” language—immortal yet draining—highlighting quirks such as sentences ending with periods and the prevalence of global variables and GOTO statements that produce spaghetti code. He also references the “COBOL Cowboys,” a dwindling cadre of veteran programmers who keep these systems running. The continued reliance on COBOL creates a strategic risk: a shrinking pool of skilled engineers threatens the stability of critical financial infrastructure. Companies face a costly choice between expensive rewrites and maintaining fragile legacy code, underscoring the urgency of talent development or system migration.