When every second matters - such as combat - players take turns describing their character’s actions. Many actions require a check of some kind (attacking, casting a spell, intimidating an enemy into retreat), each with its own DC and modifiers.

A PC may take one of each type of action per melee round, but might be forced to make checks that don’t count as actions.

• Active: Most proactive actions that require a check (stealth, attack, cast).
• Movement: You can move up to your speed (usually 30’). You can split up this distance throughout your turn.
• Quick: Brief actions which may be either used during your turn or triggered off others like the 5e reaction.

Active actions are driven by the character's choices and often require a check. Active actions include:

• Attack: The most common action to take in combat is the Attack action, whether you are swinging a sword, firing an arrow from a bow, or brawling with your fists. With this action, you make one melee or ranged attack. Certain features allow you to make more than one attack with this action.
• Cast a Spell: Spellcasters such as scholars and zealots, as well as many monsters, have access to spells and can use them to great effect in combat. Each spell has a casting time, which specifies whether the caster must use an Active action, a Quick action, minutes, or even hours to cast the spell. Casting a spell is, therefore, not necessarily an action. Most spells do have a casting time of 1 Active action, so a spellcaster often uses his or her action in combat to cast such a spell.
• Dash: When you take the Dash action, you gain extra movement for the current turn. The increase equals your speed, after applying any modifiers. With a speed of 30 feet, for example, you can move up to 60 feet on your turn if you dash. Any increase or decrease to your speed changes this additional movement by the same amount. If your speed of 30 feet is reduced to 15 feet, for instance, you can move up to 30 feet this turn if you dash.
• Disengage: If you take the Disengage action, your movement doesn't provoke opportunity attacks for the rest of the turn.
• Dodge: When you take the Dodge action, you focus entirely on avoiding attacks. Until the start of your next turn, any attack roll made against you has disadvantage if you can see the attacker, and you make Dexterity saving throws with advantage. You lose this benefit if you are incapacitated or if your speed drops to 0.
• Give Orders: You may use your action to command retainers to take special maneuvers.
• Hide: When you take the Hide action, you make a Dexterity (Stealth) check in an attempt to hide, following the rules for hiding. If you succeed, you gain certain the benefits of attacking from hiding.
• Use an Item: You may use a magic item using this action.

An active action can be “traded down” to a move or quick action, but only during your round in combat.

You can move up to your speed in feet (30’ base, load reduces) for each movement action. You can split up this movement however you would like, and can take actions in between segments of movement such as moving, then attacking, then moving again.

Some forms of special movement - swimming, crawling, climbing, or traveling in difficult terrain - force you to move at half speed (a PC with 30’ speed can climb 15’). Each load you carry above your STR score reduces your speed by 5’ and forces disadvantage on all checks.

A 10 STR, 30’ speed PC carrying 11 load would move at 25’ speed. A PC at 0’ speed is completely encumbered and can’t move at all. A movement action can be “traded down” to a quick action, but only during your round in combat.

Unlike other actions, quick actions may be triggered by another and may be resolved even when it is not that PC's round. For example, The most common form of quick action is making an attack of opportunity as an adversary withdraws. Drawing items or weapons, casting certain spells, and some class features are also quick actions. The GM can rule that certain other basic actions are quick actions.