Plastic materials are often used instead of natural products because they cost less and sometimes tend to be more durable. Very early on plant fibers have had a more extensive use than silk, wool and other animal fibers. Gradually as humans’ needs multiplied, the use of vegetable fibers increased greatly until presently they continue to be of great importance even after the onset of plastics. It is impossible to estimate the number of species of fiber plants, but over a thousand species of plants have yielded fibers in America alone, and over 800 occur in the Philippines.