CSV is a file format used to store tabular data, such as spreadsheets or databases. In a CSV file, each line represents a row of data, with each column separated by a comma. CSV files are widely used because they can be opened and read by many different software applications.

JSON (JavaScript Object Notation) is a lightweight data format used to exchange data between servers and web applications. It's a text-based format that's easy for humans to read and write, and it's often used to transmit data in APIs, web services, and other applications.

CSV and JSON are both file formats used to store and exchange data, but they have some key differences. CSV is a simple, text-based format that stores data in rows and columns, with each field separated by a comma. JSON, on the other hand, is a lightweight, text-based format that stores data as a series of key-value pairs, similar to a dictionary or object in JavaScript.

CSV and Excel are both file formats used to store tabular data, but they have some key differences. CSV files are plain text files that store data as simple text separated by commas, while Excel files are binary files that store data in a proprietary format. Excel files can contain formatting, formulas, and other features that CSV files do not support.