The const keyword modifies values. This means whenever we have an object, variable, widget, etc., we know that its underlying value or state won’t change.

To have a better understanding of const is to think in a way that const object values can be calculated at compile time. For example, 1+2 will always be equal to 3, and this fact cannot be changed. But on the other hand, the DateTime.now() function will return a different DateTime on every single function call, even if there is a difference of a nanosecond from the previous DateTime.now() function call, and hence, it is dependent on runtime.