 # What are the differences between JavaScript's Math.floor() and Math.ceil()?Ava W  const t="undefined"!=typeof HTMLImageElement&&"loading"in HTMLImageElement.prototype;if(t){const t=document.querySelectorAll("img[data-main-image]");for(let e of t){e.dataset.src&&(e.setAttribute("src",e.dataset.src),e.removeAttribute("data-src")),e.dataset.srcset&&(e.setAttribute("srcset",e.dataset.srcset),e.removeAttribute("data-srcset"));const t=e.parentNode.querySelectorAll("source[data-srcset]");for(let e of t)e.setAttribute("srcset",e.dataset.srcset),e.removeAttribute("data-srcset");e.complete&&(e.style.opacity=1,e.parentNode.parentNode.querySelector("[data-placeholder-image]").style.opacity=0)}}

JavaScript's`Math.floor()` and`Math.ceil()` are both methods of the`Math` object used for rounding numbers. Here are the differences between these two methods: 1.`Math.floor()`: - The`Math.floor()` method rounds a number down to the nearest integer less than or equal to the given value. - It always returns the largest integer less than or equal to the input value.

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Math.floor(4.9); // 4
Math.floor(-2.1); // -3
``````

In the first example,`Math.floor(4.9)` returns`4` because`4` is the largest integer less than or equal to`4.9`. In the second example,`Math.floor(-2.1)` returns`-3` because`-3` is the largest integer less than or equal to`-2.1`. 2.`Math.ceil()`: - The`Math.ceil()` method rounds a number up to the nearest integer greater than or equal to the given value. - It always returns the smallest integer greater than or equal to the input value.

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Math.ceil(4.9); // 5
Math.ceil(-2.1); // -2
``````

In the first example,`Math.ceil(4.9)` returns`5` because`5` is the smallest integer greater than or equal to`4.9`. In the second example,`Math.ceil(-2.1)` returns`-2` because`-2` is the smallest integer greater than or equal to`-2.1`. 3. Usage scenarios: -`Math.floor()` is commonly used when you need to round down a number to the nearest integer. It is useful in situations like calculating array indices or truncating decimal places. -`Math.ceil()` is often used when you want to round up a number to the nearest integer. It is useful, for example, in calculations where you need to ensure that a value is not rounded down. 4. Comparison: - When dealing with positive numbers,`Math.floor()` always rounds towards zero (downward), while`Math.ceil()` always rounds away from zero (upward). - For negative numbers, the behavior is inverted.`Math.floor()` rounds further away from zero (more negative), and`Math.ceil()` rounds closer to zero (less negative).

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Math.floor(-3.5); // -4
Math.ceil(-3.5); // -3
``````

In this example,`Math.floor(-3.5)` returns`-4` because it rounds further away from zero, while`Math.ceil(-3.5)` returns`-3` because it rounds closer to zero. Choose the appropriate method based on your rounding needs. If you want to round down to the nearest integer, use`Math.floor()`. If you need to round up to the nearest integer, use`Math.ceil()`.