To answer the first part of this question, rayon is a cellulose-based fabric manufactured from regenerated cellulose and has another name: viscose. There are various different types of rayon that can appear to be similar to natural fibers such as linen, cotton, and silk. With bamboo-derived rayon, the cellulose is obtained from bamboo fibers. This is chemically converted to a thread that can be woven and used for sheets. In other words, bamboo sheets are woven from bamboo-derived rayon threads.