Protein kinases are these enzymes found inside our body which are responsible for catalyzing phosphorylation reactions? And as we discussed previously, phosphorylation is an example of covalent modification. And this is a mechanism that our cells use to basically regulate and control the activity of enzymes and the functionality of proteins. Now, we can categorize protein kinases into two groups. On one side we have a group called dedicated protein kinases and on the other side we have a group known as multifunctional protein kinases. Now, what exactly is the difference between these two groups?