Electricity is just the most basic interaction that makes everything around us work. It is what makes all the atoms in your body, or your razor stay together, it's what makes them move around. The gravity is different and also works between anything but it's way way weaker than electricity.
What makes you breathe, or think, or eat, or your heart beat is the electric currents in your body. Those are pretty small currents, caused by small charges, that's why you need really big magnets when you image them with MRI.

Now when you have two wires they have plenty of electrons in there that are very easy to move around (in contrast if you had two pieces of wood you have similar number of electrons, but they are very very hard to move.) The only thing that's missing is something to make these electrons move in unison. That's where your power company comes into play - you pay them money, they burn some coal and get that energy that was stored into the coal converted into 'electric field' that can move electric charges between the two wires in your outlet.
Normally they can't jump through the air between the wires (but if it gets very humid they may be able to and you can get sparks from the plasma discharge). If you touch those wires though the electrons that are there under the force that the electric company has provided can just go through your body and that flow is much bigger than the small currents that make your body operate and totally disrupt them.

Sometimes you can recover from this, sometimes you can't. I guess this time around you ended in the first group

The only difference between AC and DC is that in AC the direction of the flow (or the force that causes that flow) flips back and forth 50-60 times each second.