Scales selected vertices or faces by a numeric factor.
The expansion can be optionally turned off in the up/down(Z) left/right(X) or front/back(Y) directions.
Vertices - Scales the selected vertices either from the 3D Cursor position or the Center of the selected vertices. This is the most commonly used option.
Faces - Scales the selected face size only without affecting the size of the model itself.
From Cursor - Scales the selected vertices or faces relative to the position of the 3D Cursor.
From Center - Scales the selected vertices or faces to the center of the selected vertices or faces.