Game Interface

The Diablo II interface is divided into two main areas, the Play Area and the Interface Bar. The Play Area is your view of the Diablo II world, showing events as they occur. The Interface Bar below the Play Area displays much of the important information about your character, offering quick insight into your character's state of being.
The two dominant features of the Interface Bar are the Life Orb and Mana Orb. The two Orbs show graphically how much health and mana your character posses. Mana regenerates over time, slowly refilling the Orb. Life, however, must be replinished by drinking a potion, visiting an NPC with the power to heal or other magical means.
The Primary and Secondary Attack icons just inside the Life Orb and Mana Orb show the currently selected skills/attacks assigned to the left and right mouse buttons. Left-clicking on the Attack icon will reveal a pop-up menu of skills that can be assigned to the mouse buttons.
The Stamina Bar displays the amount of stamina remaining. The yellow bar will become red when your character is near exhaustion and can be replinished simply by slowing to a walk. The Experience Bar slowly grows as the character gains experience. Once the bar reaches the right side of the meter, the character will "level up" and the bar will be reset.
Inventory

The inventory screen contains your physical inventory, the inventory in
your character's belt and the items your character is currently equiped with.
Your character is able to use/wear equipment in the following places: head, body,
waist, neck, fingers, hands, feet, primary attack/hand and secondary attack/hand.
Items obtained during play are automatically added to your inventory or worn by your character. While the inventory screen is open, however, items must be manually placed.
Every item within Diablo II occupies a fixed amount of space, limiting the
number of items your character is able to carry. Efficient spacing of items can
often create additional room for extra items. In addition to "creative spacing,"
There are several other ways to increase the number of items your character can
carry.
Stacking Items
Several "containers" available in the game will hold multiple pieces of the same
items. A "Tome of Identify," for example, can hold up to twenty Identify Scrolls.
Other items, such as keys, stack automatically. The number of items held in the
container is displayed along with the container information by holding the mouse over
the item.
Belt Inventory
Your belt inventory is displayed on the bottom of the play screen. Depending on the
type of belt or sash, your character can hold up to 16 items in this inventory. Only potions and scrolls may be placed in the belt. The four items shown can be activated by right clicking on the item or using the hot keys (numbers 1-4 on the keyboard).
Mousing over the belt inventory will open a window showing the other items in the belt. Potions or scrolls picked up during play will automatically be stacked in the slot above a similar potion or scroll. Once the stack is full, additional potions and scrolls will be placed in your character's general inventory.
Private Stash
New in Diablo II is the the "Private Stash". The stash serves as a secure place to store items and gold that you wish to keep but not carry. No other players can view or change your Private Stash. While you cannot use items stored in your Stash, the gold deposited is used along with the gold in your inventory when making purchases. The Stash will travel with you from Act to Act, and is always available in your "home" town.
Character Attributes and Skill Trees

A character's abilities and skills may be changed as a character increases in level throughout Diablo II. These attributes are controled by several statistics (Strength, Dexterity, Vitality and Energy) covered in-depth in the Character Attributes section. Skill Trees allow for personalization of your character, creating a unique combination of abilities.
General information on skill trees can be found in Skill Trees introduction with more class-specific presented in each of the characters sections.