What are the key differences between `setInterval` and `setTimeout` in JavaScript?

Delving into the Distinctions between 'setInterval' and 'setTimeout'

JavaScript provides two powerful functions, 'setInterval' and 'setTimeout', that allow developers to schedule code execution at specific intervals or after a specified delay. While seemingly similar, these functions differ significantly in their behavior.

'setTimeout' operates as a one-time event scheduler. It takes two arguments: a callback function and a time delay. Once the delay expires, the callback function is executed only once. This function is suitable for scenarios where a single execution is desired after a predetermined wait time.

In contrast, 'setInterval' is designed for repeated execution. It also takes two arguments: a callback function and a time delay. However, the key distinction lies in its behavior. 'setInterval' schedules the callback function to run repeatedly at the specified interval. It creates a loop that continues until the interval is cleared explicitly using 'clearInterval'. This function is ideal for creating recurring tasks or animations.

To illustrate the difference, consider the following code snippet:

var intervalID = setInterval(alert, 1000); // Will alert every second.
// clearInterval(intervalID); // Will clear the timer.

setTimeout(alert, 1000); // Will alert once, after a second.

In this example, the 'setInterval' function schedules the 'alert' function to run every second, creating a continuous loop. On the other hand, the 'setTimeout' function causes the 'alert' function to execute only once after a delay of one second.

By understanding the fundamental differences between 'setInterval' and 'setTimeout', developers can effectively implement code scheduling and timing mechanisms in their JavaScript applications.

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