Foliation and Layering are terms that are usually discussed when talking about the concepts of rock formation. These two processes are mostly discussed in relation to some processes during the formation of sedimentary and metamorphic rocks. Foliation occurs mostly in metamorphic rocks, and its processes are usually identified through the planar structure created when the sheets of silicate materials are aligned in a parallel form.
I guess you know that metamorphic rocks are formed from other preexisting rocks; however, the pattern of penetration created through the restructuring of some minerals is called foliation. On the other hand, layering is a common term used during the formation of some sedimentary rocks.
Layering is a process that occurs when there are layers of rocks forming over the other. When you study rocks with layering, chances are you will see different kinds of sentiments across the layers. Invariably, the patterns created by the two processes are actually their major differences.