Typed this out for my Free Company website to, hopefully, help better explain certain stats. Thought I'd post here too.
(note on the Miner and Botanist notes on STR/DEX/INT/MND; I can't remember exactly which bonuses these stats will give when you have the value or higher needed for Tree/Stone Whisperer, so I only listed "enhances gathering" rather than what they do exactly. Sorry.)
Main Attributes
Strength - Increase melee attack power. (Weapon Skills/Auto Attack)
Increases the % of damage mitigated when you parry. For Miner, enhances gathering should Stone Whisperer conditions be met.
Dexterity - Increases ranged attack power. (Ranged Weapon Skills/Ranged Auto-Attack). Increases chance of parrying and/or blocking an attack. As Botanist, enhances gathering should Tree Whisperer conditions be met.
Vitality - Increases HP. Does NOT increase Defense, nor does it affect MRD's attack power like it did in 1.0.
Intelligence - Increase magic attack power. (Fire/Ruin/Stone etc.) For Botanist, enhances gathering should Tree Whisperer conditions be met.
Mind - Increases Cure Potecy. (Cure and Physick for Arcanist.) For Miner, enhances gathering should Stone Whisperer conditions be met.
Piety - Increases MP.
Battle Stats - These stats are not affected by your main attributes at all. Example; DEX in FFXI would increase Critical Hit Rate. In FFXIV, Critcal Hite Rate can only be increased or decreased via armor/food/skills/status effects. The only exceptions to this are STR/DEX for attack power, Dex for Parry, INT for magic attack potency, and MND for Healing Magic potency.
Accuracy - Increases Physical/Ranged/Magical hit rate. The higher the number, the less likely you are to miss. (and spells can miss in this game)
Critical Hit Rate - Increases Physical/Ranged/Magical critical rate. The higher the number, the more likely you are to crit.
Determination - Increases attack power of all skills/spells you use. Also, increases HP restored when Cure/Physick are casted on you. (Meaning your determination and the caster's Mind affect cure potency)
Defense – Overall physical damage reduction. (Mainly gained through equipment/certain actions/Protect.)
Parry – Your chance to parry. Parrying reduces incoming damage by a certain percentage. (Chance to parry increases via actions, armor and Dexterity. Amount of damage% mitigated increases via actions, armor and Strength.)
Magic Defense - Overall Magical damage reduction. (Mainly gained through equipment/certain actions/Proshell (Protect from a Lv16+ CNJ/WHM.)
Attack Power – Your overall physical damage capability. Increased via actions and equipment (weapon being used being the main factor)
Skill Speed – Reduces recast time of weapon skills.
Slashing - Resistance to slashing type damage. (Swords, Axes, certain monster attack types.)
Piercing – Resistance to piercing damage. (Polearms, Arrows, certain monster attack types.)
Blunt – Resistance to blunt type damage. (Fists, Staves, Clubs, certain monster attack types.)
Attack Magic Potency - Your overall magic damage capability.
Healing Magic Potency – Your overall healing capability.
Spell Speed – Reduces cast time of magical skills.
Morale - PVP only stat. Decreases damage taken while engaged in PvP.
Gathering stats
GP(Gathering Points) - Acts as MP for Miner/Botanist. Recharges by 5 GP every 3 seconds while not gathering. While gathering, GP recovery only happens when you gather something successfully, and increases with each EXP chain. (Say you have 5 attempts at a gathering spot and you successfully gather 5 times in a row. GP would recover 1>2>3>4>5 for 15 GP; assuming you did not use any GP that gathering attempt. Now, suppose you did 5 gathering attemps, but missed the 3rd one. GP recovered would be 1>2>0>1>2. GP recovery chain resets with EXP chain while gathering.)
Gathering - Increases chance to successfully gather an item. Will also provide a bonus to certain gathering nodes with Tree/Stone Whisperer.
Perception - Increases HQ gathering rate. Will also provide a bonus to certain gathering nodes with Tree/Stone Whisperer.
Crafting Stats
CP(Crafting Points) - Acts as MP for all crafting jobs. Gauge fills completely when you change to a crafting class and when you finish crafting an item. CP does not recover during synthesis unless a CP recovery skill was used. Allows use of special crafting skills. Skill effects include increasing durability of an item, increasing Control stat each time quality of an item is increased (to increase chance of HQ item), etc.
Craftsmanship - Increases the amount of progress gained when using Basic/Standard Synthesis.
Control - Increases the amount of quality gained when using quality increasing actions. The higher quality is for a synthesis, the higher your odds of making a High-Quality version of the item is. (Using HQ materials while crafting will also boost quality prior to starting the craft. The more HQ mats used, the more the quality bar will be filled at the start.)