The main attributes of the character-distributed at the beginning of the game and greatly affect the stats of the character. In the course of pumping the character they can be improved. Each attribute is measured by a number from 1-10.
Perks-independent of attributes, affect the style of play. Each of the perks is measured by a number from 0-100. From zero, because the perk you first need to learn either from NPC or yourself (reading a book or on the game there is such a possibility). After receiving the first level perks will be upgraded by repeating the actions associated with this perk, upgraded by skill points, etc.
Ability to-are dependent on perks and attributes. Each ability can be obtained with the required number of attributes and perks. For example, the ability to "Casanova" allows you to enter into a romantic relationship with several girls at once, without fear that one of the girls will break up with you. You can get this perk by upgrading charisma and eloquence.