Parquet is a columnar storage file format designed for efficient data processing and storage. It is commonly used in big data frameworks like Apache Hadoop and Apache Spark. By organizing data in columns rather than rows, Parquet allows for better compression and faster query performance, especially for analytical workloads. This format supports complex data types and is optimized for read-heavy operations, making it ideal for data warehousing and analytics. Parquet files are also compatible with various programming languages and tools, enhancing their versatility in data engineering and data science applications.