--- title: "What is the difference between a \"closure\" and a \"lambda\"?" description: "What is the difference between a \"closure\" and a \"lambda\"?" author: "Ashutosh Patel" published: 2025-03-24 updated: 2025-03-25 canonical: https://www.mindstick.com/forum/161337/what-is-the-difference-between-a-closure-and-a-lambda category: "javascript" tags: ["javascript", "lambda expression", "Lambda Functions"] reading_time: 2 minutes --- # What is the difference between a "closure" and a "lambda"? What is the [difference](https://www.mindstick.com/articles/157114/good-news-or-bad-news-and-the-difference-is) between a '`closure`' and a '`lambda`'? ## Replies ### Reply by Khushi Singh The concept of **closures** remains different from the concept of **lambdas**, although both relate to functions. A function known as a [closure](https://www.mindstick.com/blog/303657/javascript-closure-what-is-it) preserves variables created within its surrounding scope even after its parent scope exits. JavaScript, Python, and various other programming languages provide functions with the ability to recall their creation environment through closures. This functionality allows both state preservation between function calls and encapsulation features. Closures serve as functional tools throughout event handlers and callbacks, and also within functional programming designs. A [lambda](https://www.mindstick.com/blog/304513/what-are-lambda-expressions-in-java-how-do-they-simplify-code) stands as an unnamed function since it does without defined formal definitions. People use this syntax for temporary execution sequences that could be simplified through standard functions. [Lambdas function](https://www.mindstick.com/articles/897/lambda-expression-in-c-sharp) as inline function definitions within Python, JavaScript, and C# for use in collection processing operations such as filtering and mapping, and reduction. A lambda expression requires the enclosed variables to form a closure when it captures them within its memory space. A closure helps functions reuse variables from their outer context as it retains stored variables in memory, whereas a lambda function defines brief anonymous definitions. Lambda functions transform into closures when they capture surrounding scope variables, but lambdas do not need to capture variables to be closures, and closures do not require the use of lambdas. --- Original Source: https://www.mindstick.com/forum/161337/what-is-the-difference-between-a-closure-and-a-lambda Copyright © MindStick Software Pvt. Ltd. This Markdown version is provided for developers, AI systems, and offline reading.