Runge-Kutta 4 explanation

I'm a game developer and I need to write a solar system simulation. Unfortunately I'm not very good at math and most importantly I haven't got to differential equations in my maths classes at school yet. After some research I came to the conclusion the best method for me is the common Runge-Kutta. I've read a lot about it and from what I understand it's a method that divides a timestep into 3 parts, calculating the values of the function (in this case position and orbital velocity) at each of these parts and then doing something (I haven't really understood how is this any different than Euler with a smaller timestep). I really can't understand the explanations on wiki or other places because they all use formulas which don't say anything to me.

Now since I have to adapt it into code, I'd like to understand it fully, so I really need a live person to explain it to me. Bullet points would be perfect!

• I'm a game developer and I need to write a solar system simulation. Unfortunately I'm not very good at math , that's really surprising to me :-) Mar 18, 2013 at 17:47
• Runge-Kutta basically computes integration numerically. Let's forget the solar system, do you know how to implement a two celestial body simulation? Mar 18, 2013 at 17:56
• Related question on stackoverflow.com: Runge-Kutta (RK4) integration for game physics
– GEL
Mar 18, 2013 at 18:17
• Abhijit: Game development doesn't usually require a deep knowledge of math, I got by just by searching for solutions of other people, and most of the others do so as well. ShuhaoCao: There's little difference between simulating 2 or 5000 bodies if I don't know how to keep my orbits stable. lewellen: I saw that earlier, and it's the most understandable explanation I saw so far, but there are too many technical terms and everything is explained in a too generic way.
– Lama
Mar 18, 2013 at 18:46