# Lambda Functions in ksqlDB for Confluent Platform A lambda function, or “lambda” for short, is a simple inline function you can apply to input values. For example, you can use a lambda function to transform each element of a collection, filter the elements of a collection, or reduce a collection to a single value. The advantage of a lambda is that it expresses a user-defined feature without requiring you to implement a full [UDF](../how-to-guides/create-a-user-defined-function.md#ksqldb-how-to-create-a-udf). Learn how to use lambda functions in the [how-to guide](../how-to-guides/use-lambda-functions.md#ksqldb-how-to-use-lambda-functions).