Data structures & formats · reviewed in July 2026
CSV
CSV (comma-separated values) is a plain-text file format for storing tabular data, where each line is a row and columns are separated by a delimiter character, usually a comma. It's one of the most common formats for exchanging data between spreadsheets, databases, and analysis scripts.
import pandas as pd
df = pd.read_csv("customers.csv", sep=",")
df.head()Frequently asked questions
How do you read a CSV in pandas?
With pd.read_csv('file.csv'), which loads the file directly into a DataFrame, inferring each column's type.
Is the delimiter always a comma?
Not necessarily. Some countries and tools use a semicolon to avoid clashing with a decimal comma; pd.read_csv accepts a sep parameter to specify the correct delimiter.
What are CSV's limitations compared to other formats?
It stores no data types or metadata (everything reads back as text), doesn't handle nested data well, and tends to be larger than compressed binary formats like Parquet for big volumes.