This is the most basic Jitgi in Taekwondo. Technical point is that you should move with one leg only, corrupting your balance in each movement. Beginners has disposition to use two legs together, for they see another move actually two legs, but this is not the point. If they intend to use two legs, they will fail to get this technique. Let me tell you again, that the point is to lift one foot only, so that you can corrupt your balance to forward or backward.
The meaning of Jitgi is controlling distance.