Different proteins are formed from different orders of amino acids. As there are varieties of amino acids, they fit in everywhere possible in a polymer chain. This way, different proteins are formed.
Every protein is made by ribosomes, so google proteins and pick the first 10 that pop up. Some good ones are hemoglobin, ATP sythase, DNA Helicase, ligase, and reverse transcriptase.
Most proteins are linear polymers built from series of up to 20 different L-α-amino acids. All amino acids possess common structural features, including an α-carbon to which an amino group, a...