Kinetic energy is just the fancy scientific way of saying movement. And I mean that. If something has a store of kinetic energy, then it is moving, or in motion. Kinetic energy is probably the most common store of energy, in the sense that it is happening all the time, all around us, and every time you move or move something, then other stores of energy are being transferred into kinetic energy, whether it be you using chemical energy to move your arm, or pushing something off a table and transferring gravitational potential energy into kinetic energy, everything you do is somehow linked to movement.
Kinetic energy can come in different forms, such as thermal energy and sound. Why? Well because thermal energy is measured by the energy and movement of molecules in an object, and sound is the movement of molecules through a medium, with the keyword being movement. Kinetic energy can also be very helpful in transferring other stores of energy into usable electricity. I will go into more detail in another post, but the basic idea is that you heat up water using a fuel and the steam rises and spins turbines which are connected to a magnet. You may or not know that when you spin a magnet inside a wire, it creates electricity. This whole process is made possible by kinetic energy, and without it, you would not be reading this right now, or at all.
Thank you for reading this post, and as always, please visit other, more official websites that will give you a better, more detailed explanation.