So far we've looked at decisions that a script can make about what code to execute. Scripts can also decide how many times to execute a block of code. Loop statements are designed to enable you to achieve repetitive tasks. A loop will continue to operate until a condition is achieved, or you explicitly choose to exit the loop.

The while Statement

The while statement looks similar in structure to a basic if statement:

while (expression) {
      // do something

However, unlike an if statement, a while statement will execute for as long as the expression evaluates to true, over and over again if need be. Each execution of a code block within a loop is called an iteration. Within the block, you usually change something that affects the while ...

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