Check out example codes for "css overflow hide scrollbar when not needed". It will help you in understanding the concepts better.

Code Example 1

/*
The overflow property has the following values:

visible - Default. The overflow is not clipped. The content renders outside the element's box
hidden - The overflow is clipped, and the rest of the content will be invisible
scroll - The overflow is clipped, and a scrollbar is added to see the rest of the content
auto - Similar to scroll, but it adds scrollbars only when necessary

*/

div {
  overflow: auto;
}

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