What is the purpose of a while loop in programming?

The purpose of a while loop in programming is to repeat an operation for an unspecified number of times. This loop continues to execute a block of code as long as a specified condition evaluates to true. Since the number of iterations is not predetermined, a while loop is particularly useful when the number of repetitions depends on dynamic factors, such as user input or the state of a data structure.

This approach allows programmers to handle situations where the exact number of iterations cannot be known before the loop starts. For example, one might use a while loop to read user input until the user indicates they are finished, or to process elements in a collection until a certain condition is met. The flexibility of a while loop makes it a fundamental control structure in programming.