The Free Action and Its Relatives
As noted in Part One, a free action is something you do during your turn that takes hardly any time at all. Many people believe that a free action never provokes an attack of opportunity, but that is not a feature of free actions. It is true, however, that free actions rarely provoke attacks of opportunity. For example, none of the free actions noted on page 144 of the Player's Handbook provokes attacks of opportunity.
You usually can perform a free action before, after, or during another action, circumstances permitting. For example, dropping an item is a free action. If you also move during your turn, you could drop an item at any point during the move. On the other hand, speaking a few words also is a free action. If you move, you could speak at any point during your move, but you could not speak while simultaneously casting a spell with a verbal component. If you tried to do so, you'd interrupt your own spell. You could, however, speak a few words before or after casting the spell. Likewise, you can cast only one spell at a time. You can't cast a quickened spell while casting another spell. When in doubt about when a free action can occur, the player and DM should discuss the matter.
You cannot use a free action during another creature's turn. Speaking is an exception; you can speak during another creature's turn (see page 144 in the Player's Handbook). Remember, however, that you're limited to just a few sentences. If you know where an invisible creature lurks, you can't tell a colleague where the creature is the moment your colleague acts (you could ready such an action, however -- see Part Four -- and you'd really be using a variant of the Aid Another action).
It's Like a Free Action but It Isn't
The Expanded Psionics Handbook introduced two new kinds of actions that are very similar to free actions. Like free actions, these actions take little or no time. Unlike free actions, there are strict limits on how many of these actions you can use in a single turn and when you can use them. Here's an overview:
Swift Actions: You can perform one (and only one) swift action during your turn. A swift action is otherwise just like a free action.
Immediate Actions: You can use an immediate action any time, even during another creature's turn. If you use an immediate action during your turn, you cannot use a swift action during your next turn. You cannot use another swift or immediate action until after your next turn
Drawing or Sheathing a Weapon: Drawing a weapon so that you can use it in combat, or putting it away so that you have a free hand, usually is a move action. If you have a base attack bonus of +1 or higher, drawing (but not sheathing) a weapon is a nonaction that you can take along with a regular move (that is, a move action that you use to move up to your speed across the battlefield). If you have the Two-Weapon Fighting feat, you can draw two weapons (either light or one-handed weapons) either as a move action or as a nonaction along with a regular move.
The draw a weapon action (and nonaction) also applies to weaponlike objects carried in easy reach. The rules don't give much guidance about which objects are "weaponlike," other than to use a wand as an example. As a practical matter, I suggest treating any object that is no bigger than a weapon for the character as weaponlike for this purpose. To be retrieved as a weapon, the weaponlike object also has to be stored in some convenient place, such as a sheath or loop in a belt or on some kind of harness or bandoleer.
Drawing ammunition for use with a ranged weapon (such as arrows, bolts, sling bullets, or shuriken) is a free action.
The Quick Draw feat allows you to draw (but not sheathe) a weapon as a free action during your turn. If you also have the Two-Weapon Fighting feat, you can draw two weapons as a free action during your turn. Though the rules don't say so, it is reasonable to assume that you also can use Quick Draw to draw weaponlike objects.
Readying or Loosing a Shield: Strapping a shield to your arm to gain its shield bonus to your Armor Class is a move action that does not provoke an attack of opportunity. The rules don't specifically say so, but to ready a shield as a move action you must carry it on your person (perhaps strapped to your back). If you pick up a shield off the ground, that takes a separate move action that provokes an attack of opportunity.
Unstrapping and dropping a shield so you can use your shield hand for another purpose requires a move action that does not provoke an attack of opportunity (to unstrap it) and a free action (to drop it). You also can merely loose the shield and keep it on your person, usually by slinging it over your back by a strap.
If you have a base attack bonus of +1 or higher, you can ready or loose a shield as a free action combined with a regular move.
Manipulating an Item: Moving, lifting, storing, retrieving, or otherwise handling an item is a move action. See Table 8-2 in the Player's Handbook for variations on this action and which variations provoke attacks of opportunity
