One of the reasons a person might choose metafiles is because they scale when a drawing size is changed (either shrinking, or expanding) with little change in their clarity. This is because each of the elements (including text) is discrete. Choosing save to a bitmap has a different effect in that you can shrink with some change, but expanding often yields (to some) an unacceptable distortion. However a bitmap is intended to stay the size it is saved as, since it is a single picture.
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