Can someone explain: What is a CSV file and how is it used? or Newbie question: What is a CSV and why

CSV = Comma-Separated Values. What is a CSV? Basically, the simplest way to share tabular data without locking it into one program.

It’s everywhere because it’s open and flexible. Excel, databases, Python scripts—all can chew on a CSV without issues.

For opening, I’d recommend Google Sheets (web-based, no install) or a proper CSV editor like TableTool if you deal with them often.