An item group is a group of similar items, used by survivors. All items from an item group share the same add-ons and usually serve the same purpose.

Currenty, the game contains the following item groups:

• Toolboxes

• Med-Kits

• Keys

• Flashlights

• Maps

• Firecrackers

In the design phase of the data file, I considered just making a list of items and add-ons and then somehow cross-reference then. I had some ideas, but ultimately thought about how the wiki did it. And yes, they have a category on "Toolboxes", because they all serve a similar purpose.

Items are not distributed evenly with item groups. The reason for this is that item groups are picked randomly (and fairly) and then one item is picked out of a random group. This means that an item from a small item group (e.g. firecrackers or maps) are more likely to be picked than an item from a large item group (e.g. toolboxes or med-kits).

Since there are currently 5 item groups, the chance of one item group to be picked is 1/5. The largest item group is toolboxes with 6 items, and the smallest are the maps (and the firecrackers). As such, the chance of picking an "Engineer’s Toolbox" is 1/5 * 1/6, which is 0.033 or 3.33%. The chance of picking a "Rainbow Map" is 1/5 * 1/2, which is 0.1 or 10%.

Because I think it makes sense to equally distribute items which all have a unique feel to them. Your playstyle is different if you have a map, a toolbox or a flashlight. Your playstyle is not different if you have an Engineer’s Toolbox in comparison to a Worn-Out Toolbox.