Protein exists as achain consisting of amino acids linked by a peptide bond. These chains can be in random shapes. But what makes them biologically functional is the shape it takes up when they are acted upon by a ribosome. are found in all living cells and they perform protein synthesis. The exact of a protein is crucial for its function. There can be parts of the functional protein that still remains unfolded. From a physical point of view, the unfolded state has the highest entropy hence it's natural state. There is a certain amount of energy that is required for the folding to happen and reduce its entropy. Folding can be triggered by hydrophobic reactions. Molecular chaperones are a class of proteins that aid in the correct folding of the protein. Neurogenerative diseases have been linked to the misfolding of proteins.
The process of protein folding is not. There are many variables build into this process that makes it really hard to predict the correct functional folding for a protein. It is estimated that a natural protein can have 10300 possible combinations. It is not truly random but rather a model that can replicate this process is . Understanding this fundamental biological process can help in developing new medicines and managing new environment.