lmao check yourself guy. “Return to grade school to learn how to use a comma”
Many countries, particularly in Europe, South America, and some parts of Africa, use a comma (,) as the decimal separator, while the US and UK use a period (.).
Here's a list of some countries that use a comma as the decimal separator:
Europe:
Albania, Austria, Belgium, Bosnia, Bulgaria, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Italy, Lithuania, Netherlands (for non-currency numbers), Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, and Sweden.
Maybe you should learn more about other cultures?