Config of armor and ammo

[bdfy1]

There's not much info in SnYper config's tutorial.
Can anyone give me quick explanation how to configure armor and what everyline means on this example ? there're some comments , but I still can't understand most.

armor=505;
      armorstructural=1;
      class HitEngine {armor=0.5;material=60;name=engine;passThrough=1;}
                class HitHull {armor=0.46;material=50;name=hull;passThrough=1;};
      class HitTurret {armor=0.5;material=51;name=turet;passThrough=1;};
      class HitGun {armor=0.425;material=52;name=gun;passThrough=1;};
      class HitLTrack {armor=0.2;material=53;name=pasL;passThrough=1;};
      class HitRTrack {armor=0.2;material=54;name=pasP;passThrough=1;}; //material bil 54
      armorHull=0.5;
      armorTurret=0.5;
      armorGun=0.425; // hitpoints (relative to overall armor)
      armorEngine=0.5;
      armorLights=0.01;
      armorTracks=0.20;