CSV — Comma-Separated Values
CSV is the simplest tabular data format: plain text where each line is a row and commas separate the columns. Values containing commas or line breaks are wrapped in quotes. That's the whole format — which is exactly why every database, spreadsheet, analytics tool and programming language supports it.
CSV carries data only: no formatting, no formulas, no types beyond what the consuming application infers.
What CSV files are used for
- Exporting and importing data between systems
- Database dumps and bulk uploads
- Data science and scripting workflows
- The common denominator when two tools share no other format
Advantages
- Universally supported, human-readable, easy to generate and parse
- Compact and streams well for large datasets
- Diff-able and version-control friendly
Limitations
- No types: leading zeros, dates and large numbers are easily mangled on import
- One table per file — no multiple sheets
- Delimiter and encoding ambiguity (semicolon vs comma, UTF-8 vs legacy) causes real-world breakage
How to open a CSV file
Spreadsheet apps open CSV directly, but importing carelessly can mangle dates and leading zeros. For working with the data in Excel, converting CSV to XLSX first gives you a proper workbook from the start.