Function Parameters

Most functions need input data to work with. A function that calculates area needs to know the dimensions. A function that formats names needs to know the name. Parameters are variables that receive values when you call the function. They appear inside the parentheses in the function definition and act as placeholders for the actual values you will provide. Two terms that beginners often mix up are parameters and arguments. They refer to different sides of the same coin. Multiple Parameters Functions can accept multiple parameters, separated by commas. When calling the function, you must provide arguments in the same order as the parameters are defined: The first argument becomes the first parameter, the second argument becomes the second parameter, and so on. This is called positional mat

About This Interactive Section

This section is part of the Functional Programming: Beginner lesson on DataDriven, a free data engineering interview prep platform. Each section includes explanations, worked examples, and hands-on code challenges that execute in real time. SQL queries run against a live PostgreSQL database. Python runs in a sandboxed Docker container. Data modeling problems validate against interactive schema canvases. All content is framed around what data engineering interviewers actually test at companies like Meta, Google, Amazon, Netflix, Stripe, and Databricks.

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