There are two primary types of overwriting: 1 replacing text, and 2 replacing files. However, some programs allow you to change the standard behavior from insert to overwrite or "overtype".
If you choose select Overwrite, the old files will be replaced by the new ones. While override is very useful for polymorphism. Override To suppress; to destroy; to supersede; to annul; to nullify; as, one law overrides another; to override a veto.
But I think the overload and overwrite are fake concepts.
After all, in terms of programming, the first approach refers to Overriding since you add some new BEHAVIORS to your cars while keeping the prior behaviors which the car had, whereas the second approach refers to Overwriting since you want to change the behavior s entirely, and develop new features from the scratch.
Similarly, when moving files to a folder, the operating system may ask you if you would like to overwrite existing files with the same filenames.