Biodegradable polymer which, edible films have gained more attention due to their environmentally-friendly characteristics, vast variety and availability, non-toxicity, and low cost. Biodegradable polymers have a long history, and since many are natural products, the precise timeline of their discovery and use cannot be accurately traced. One of the first medicinal uses of a biodegradable polymer was the catgut suture, which dates back to at least 100 AD. The first catgut sutures were made from the intestines of sheep, but modern catgut sutures are made from purified collagen extracted from the small intestines of cattle, sheep, or goats. The concept of synthetic
Musical instrument the start of a hunt does so without thought of the modern notion of "making music". Musical instruments are constructed in a broad array of styles and shapes, using many different materials. Early musical instruments were made from "found objects" such a shells and plant parts. As instruments evolved, so did the selection and quality of materials. Virtually every material in nature has been used by at least one culture to make musical instruments. One plays a musical instrument by interacting with it in some way—for example, by plucking the strings on a string instrument. Researchers have discovered archaeological evidence