There are three types on the basis of composition :
1. Simple proteins 2. Conjugated proteins 3. Derived proteins.
1. Simple proteins. Simple proteins consist of only amino acids or their derivatives.
2. Conjugated proteins. These consist of simple proteins in combination with some non-protein component. The non-protein groups are called prosthetic groups.
3. Derived proteins. These are derived from pre-existing proteins either by partial hydrolysis or by coagulation.