This is the basic layout for the Create Your Own Class contest type of thingy I am holding. The stats are as follows (going clockwise): Strength, Agility, Stamina, Defense, Dexterity, and Intelligence.
The difference between Agility and Dexterity is basic speed versus flexibility. So where Agility may improve your chances of moving faster, having a higher Dexterity would make you able to perform more complex dodges and attack chains.
Stamina is not the same as Mana. Stamina in fact is a measure of how long you can do actions until your body gets worn out. Just as in the real world.
If I spelled anything wrong here, please let me know, I kinda typed this up quickly.
There is a journal about it that I posted, if you read through it, you may understand a bit more. But basically you are making up a class for a video game character.