First, we'll go over the inventory and we'll see just what each part is.
Top Left: Equip
The top left shows what equipments you have. Currently, I have my R3 equips. I'll explain ranking to you later. In the middle, right at the feet of my character are 4 slots, each filled with something. These are the jewelry slots and they're separate from the equip slots only because there was nowhere else to put them. If you hover over each equip, you'll get something that looks like this.
Now this is a description of my dagger. As you can see in the upper left hand corner, it is a Rank III weapon, used for people who are R3 or, level 50+.
+4 means I was able to enchant it 4 times with cubes. If you want to take a little detour, you can click on the section labeled "Upgrading/Enchanting" to see what I mean. Otherwise, I'll explain it later.
Right after it it says Level 10. That means I upgraded this weapon to level 10. If you upgrade weapons, they obviously get better. The max level is level 10 and it starts as a level 1 weapon. It costs money to upgrade as you will see in the "upgrading/enchanting" section.
Right below it is the word "Dirk". That just shows what kind of a weapon it is. If it was a spear, it'd say "Spear".
Now if you look carefully, you can see I have a shield and a dirk. You cannot have a spear and a shield simply because a spear is a two-handed weapon. Two-handed weapons require... two hands. So obviously you can't hold a shield. Other Two-handed weapons include Staffs, Axes, Swords, and Bows. (Bow's technically aren't, but you're not allowed to use a bow and a shield. Besides, what would you do with the shield?)
Moving on down you see the Limit Level. Limit level is the level that you can start using the weapon at. In this case, you can start using this weapon at level 50.
Right below it is the Rec. Level, or recommended level. This has to do with the orange numbers. Move on down and you'll see the P.atk of this weapon.
Bottom Half: Items
Well, this is the bottom half of the inventory screen and it shows some of the items I have. I'll place some of them down here for you and describe what they are.
This here is a Ring. It is currently un-equipped
This here is my robe. It is currently equipped. Notice the big "E". To equip things, you simply double-click the item you want equipped.
This is a pet card. It is currently not equipped.
This is a pet-weapon/armor. Notice the yellow frame and yellow thing in the upper-left hand corner. Indicates that this item is for pet use only.
This is a skill card. Skill cards increase the power of some skills.
This is a Force Chip. Force chips weaken the opponent.
This is a resurrection scroll. Use it to bring dead stuff back to life. To use scrolls, you have to click on a target and use it. Scrolls can be used on other targets, unlike potions. This item has a cool time, meaning you can use a scroll every minute or so. Some items have faster cool times, like Force Chips.
This is a wind potion. Makes you run faster. Potions are for self-use only. You cannot use it on other players. Like scrolls, this item has a cool time. Double-click a potion to use it.
These, obviously, are not all the items in game but rather, a sample of them.
At the very top, you see a few tabs. These are used to categorize your items. If you want to see all your items, you just use "Whole". If you want to see just your equips, you press "Equip". If you want to see items you can consume, use the "Consum" tab. And so on and so forth.
Bottom Bars: Combination and Wt/R
The combination button will bring up the combination menu used to combine/enchant things. I'll go over the use of this menu later on.
Wt/R are, respectively, Weight and Rupees. Weight shows how much weight you are currently holding as a fraction over the maximum amount of weight you can hold.
Rupees are the currency of Rappelz and that just shows how much money you have.
Item Box
If you use Cash Shop or collect a prize from the achievement shop, you can pick up your item from this area.