They're pretty self explainitoy. It's stuffs that in most RPGs.
For example, Dex increases you accuracy and it effects how often you crit. Agilirty determines how quik you are in combat, hence higher Agility charcter act before low agility ones. Strength effects how hard you hit with a weapon (and some techs too) and Intellegece effects how good a character is at spells, the higher the intellegence the more they heal with healing spells and the more damage their offensive spells do.
Did I explain it decent?