In Final Fantasy XIV, whenever you encounter monsters (or mobs in MMORPG terms), you will do battle seamlessly right where you are. Not all monsters will attack you on sight, as you will need to attack them first in order for them to start attacking you.
As for when you start attacking, there are many options. Every player has three main stats during battle, which are Hit Points (HP), Magic Points (MP) and Technical Points (TP). If the player's HP is reduced to 0, then they are considered dead and may be revived if they have other players in their party.
Every player's character has skills that they can assign to hotkeys (0-9 on PC, L2/R2 in conjunction with face buttons on PS3). Every skill has a cast time, recast time and a certain amount of MP and/or TP, both of which will replenish automatically over time. Every character has an auto-attack command that will enable them to continually attack the target until they either die or the character dies.
