The pack inventory, backpack or simply inventory represents all items currently carried by the player. All Angband variants have a pack inventory, but its size and other details vary from variant to variant.
The purpose of the pack inventory is to allow the player character to carry and access useful items during their adventures. These items can be spellbooks, magical potions or scrolls, magic devices, powerful equipment discovered in the dungeon, or something more mundane like food or flasks of oil.
In Vanilla Angband and most variants, the pack inventory can be viewed by pressing the 'i' key. The pack inventory is the most visible inventory during the game, and object prompts that allow selecting items from a variety of different inventories generally default to it; for this reason, it is often called simply inventory, although this term can also refer to other similar item lists such as shop inventories, home inventories, equipment or even lists of floor items.
The pack inventory has been available as a subwindow option since subwindows were first introduced in Angband 2.8.0.
The pack inventory has a limited number of inventory slots, each of which can contain either one item or one stack of similar items. Both the stacking rules and the number of available slots depend on the version and variant.
In Angband's predecessors, Moria and UMoria, pack inventory slots were capped to 22, a practical limit derived simply from the standard size of the display terminal (24 rows, including one header line and one line for listing available commands). Angband 2.7.4 increased the slot limit to 23, removing the line listing commands; this is the traditional Angband slot limit, and still remains current in Vanilla Angband and many variants. PosChengband and its derivatives have a larger inventory of 26 slots (one for each letter in the English alphabet), although in FrogComposband some characters have smaller inventories (three inventory slots are deducted from Alchemists, and one each from Werewolves and Igors). Projectiles in quivers count towards the 23-slot limit in Vanilla Angband, but not in PosChengband or FrogComposband.
There is no hard limit on the total weight of the items that can be carried in the backpack; but in practice a character's Strength does provide a soft limit, especially in the early game when Strength and Speed are still low. Carrying more weight than allowed by Strength reduces the player's speed through overburdening.
Item loss from pack inventory
Items in the inventory are less susceptible to damage than items on the floor, but can still be either destroyed by elemental attacks or stolen by a thief.
Artifacts cannot be destroyed or stolen, and items that resist or provide resistance to an element cannot be damaged by that element. Elemental resistances from equipment may fully or partially protect against elemental item destruction or provide no protection at all, depending on the variant and level of resistance.
Theft can be defended against through a special saving throw, based on the player's level and Dexterity. As a general rule, a Dexterity of 18/150 provides theft immunity regardless of level, and a Dexterity of 18/100 provides theft immunity at level 50; these theft protection calculations have remained unchanged in Vanilla Angband since Angband 2.7.9v4, and are also identical in most variants. In FrogComposband, Lawyers and Ninja-Lawyers have innate theft immunity regardless of their dexterity.
Object selection from pack inventory
Most commands that prompt for an object, such as Drop Item, Wield/Wear Item or Inspect Item, default to the pack inventory. The '/' key can be used to cycle between inventories, and reach the backpack if some other inventory is the default.
The desired object is selected by pressing its label key in the object prompt; label keys usually run from 'a' for the first item to 'w' for the 23rd item (or even 'z' for the 26th item), but most variants allow using object inscriptions to specify a different label for a given command or for all commands.