4 basic transformations to repeat and maintain symmetry along a strip:
Euclidean plane isometry is any way of transforming the plane without “deforming” it.
translation
rigid motion along the strip
the pattern slides
reflection
mirros across a line
horisontal
vertical
glide
reflection
reflect line
translate along strip
rotation
90 degree increments
used in the 7 frieze groups
used in the 17 wallpaper groups
