The classification of art into functional and non-functional depends on:
Answer Details
Art is classified as functional or non-functional based on the purpose it serves. Functional art (also called applied art) serves a practical, utilitarian purpose beyond aesthetics - examples include furniture, pottery, architecture, textile design, and jewellery. Non-functional art (also called fine art) is created primarily for aesthetic contemplation and intellectual or emotional engagement - examples include paintings, sculptures made purely for display, and art installations.
The tools used to create an artwork do not determine whether it is functional or non-functional; a potter and a sculptor may use similar tools, yet one produces a functional water jug while the other produces a decorative figure. The size of an artwork is irrelevant to this classification - a small decorative pendant and a large building are both functional if they serve a practical purpose. The colour applied is a stylistic choice that does not change whether an object has a utilitarian function.
The key distinction is always whether the artwork is intended to fulfil a practical need or exists primarily as an object of aesthetic appreciation.