What transformation involves both reflection and translation?

A glide reflection is a transformation that combines both a reflection and a translation. In this process, an object is first reflected across a line (the axis of reflection) and then translated along that line. This means that the shape not only flips over a specific axis but also shifts its position in space.

To visualize this, imagine reflecting a shape like a triangle over a straight line. After this reflection, if you then move the reflected triangle some distance along the direction parallel to the axis, you create a glide reflection.

This transformation is unique because it maintains the overall shape and size of the figure while altering its position, which is fundamental in various applications in geometry and symmetry. Other transformation types like rotation, dilation, and shear involve different operations that do not specifically include both reflection and translation.