Let's start with a simple definition of what the most commonly known protein consists of and what it actually is and does.
Genes are the base of organic compounds structured from ammino acids (essential types of acid gained from meat) which are arranged in a linear chain and joined together by peptide bonds (also named an amide bond; where a bond is formed between two molecules and when the carobxyl group(a set of four molecules bonded together in the ammino acid) reacts with the amine group (an organic compound that contains a basic Nitrogen atom with a lone pair) of the other molecule, water (H20) is released) between the carboxyl and amino groups of adjacent (side to side) residues (a monomer within the polymeric chain in the protein).
Now the most important thing about such a protein is that a cell makes proteins by stringing amino acids together in the right order. Proteins control vital processes in our body for example: enzymes are proteins. Each separate gene in the 23 chromosomes, say, is a chemical instruction on how to make a particular protein.
Proteins can be different in many ways from each other. (of course, the obvious of these would be the creation of different proteins from the ammino acids; our body could make billions of them, but we use only 20) but their structure can be quite different: they have their primary structure, then they have secondary structures (regularly repeating structures stabilised by Hydrogen bonds)they have the tertiary and quaternary structure also. Look on this << page for more information on the varying structures of proteins.
Of all the cell functions of proteins the most commonly known one is the enzyme which catalyses (basically allowing particles a surface to stick to where they can collide easier, thus making the reaction quicker)chemical reactions.
Cell signalling is also a function of proteins. proteins such as insulin (a medicine for the disease diabetes)are extracellular proteins that send a signal from the cell they were created from to other cells in distant tissues.
Visit this page for a more detailed explanation on the creation, behaviour and pin-point overview of proteins: