Exploring Glide Reflections
A glide reflection is a special composition of a reflection and a translation.
Click the boxes to see the translation and the reflection that make up this glide reflection.
Note: This vector is horizontal but a glide reflection can have any vector as long as it is parallel to the line of reflection.
http://www.maa.org/sites/default/files/images/upload_library/47/Crowe/GeoGebra_Activity_4.html by Cheryll E. Crowe, Eastern Kentucky University