If you specify a 1 after, the NPC that's on the floor will be brought back to life - meaning it will have all the same items in its inventory it had when it died and all of the same characteristics that it gained since it first spawned. If you don't specify any number, or you enter 0, a completely new copy of the NPC you resurrect will be spawned (new items, etc).
The resurrect command is used to resurrect NPCs after they have died. Kill 00078783 How to Resurrect NPCs and Your Character with Commands After making sure you have your target selected (by clicking on it with the console open), you'd type the following command: Let's say you want the NPC with reference ID 00078783 to be the killer of your target. You can find out an NPC's reference ID by clicking on it when the console is open - it will appear in brackets ( more reference ID help).
If you wish to specify a killer (the thing that killed the NPC you are killing with commands), enter its reference ID after the command (separated by a space).