What best describes a while loop?

A while loop is characterized by its ability to repeat execution of a block of code as long as a given condition evaluates to True. This means that the loop will continue to run indefinitely until the specified condition changes to False. This capability allows for very flexible control over how many times the loop runs, as it is not limited to a predetermined count but can depend on dynamic conditions that may change with each iteration.

In contrast, other types of loops have different functionalities. For instance, some loops are designed to execute a specific number of times or iterate over a collection of items, which does not align with the behavior of a while loop. An important distinction is that while loops are particularly useful when the number of iterations is not known at the start and is contingent upon conditions that can change during execution.