TSV
Like CSV, but values are separated by tab characters instead of commas. Preferred when the data itself contains commas, common in scientific and database exports.
TSV (tab-separated values) is CSV's close cousin: the same plain-text, one-row-per-line idea, but the delimiter is a tab. Its advantage is that tabs almost never appear inside real values, so unlike CSV it usually needs no quoting at all, which makes it simpler and less ambiguous to parse.
That is why TSV is the default in domains where values routinely contain commas, scientific datasets, bioinformatics pipelines, and the COPY/dump output of databases like Postgres and MySQL. The downside is recognition: hand a TSV to a consumer tool that assumes commas and it opens as a single column. It also shares CSV's deeper limit, no types, formulas, or formatting.