Some Fonts made for use with personal computers created the "0" character extra squared at the perimeters, like a rectangle, and the "O" character far more rounded. An extra difference is built in falsification-hindering typeface as used on German automobile selection plates by slitting open the digit 0 on https://financefeeds.com/global-fx-market-summary-geopolitical-tensions-fed-speculative-sentiment-20-june-2025/