Amino acids, of which there are around 20, bond together to make a long chain. This process can also be called protein synthesis.
The bonds between amino acids are generally known as amide bonds, but in the specific case of amino acids making up a protein, they have a special name; peptide bonds.
The amino acids join together to make a polypeptide initially, a long chain of amino acids, and intermolecular forces in these molecules allow them to fold up into a specific shape.
The shape of a polypeptide chain, the way in which in folds, is key to its function. Once it has folded into its specific shape, it is then known as a protein.
Either a polypeptide or a protein would be acceptable answers to this question.
