The term “natural fibres” is used collectively to describe fibres of animal or plant origin (including fruit, leaf, seed and stem), such as coconut, bamboo, hair, hemp, sisal, jute, silk and flax.

Natural fibres are typically non-uniform with large fibre-to-fibre variation, have high tensile strength and water absorption as well as anisotropic properties. These characteristics require a different approach for dimensional and mechanical analysis compared to regular, repeatable fibres such as carbon.