Specialties
These represent your mastery of a particular/specific aspect of a Skill. They are an opportunity to more uniquely define your character's talents.
It can be any field in which you are:
exceptionally practiced
naturally gifted
engaged in deeper study
trained in specific tool/equipment use
etc.
If you are attempting a task that falls within your one of your Specialties, you will receive a small bonus on your roll. This bonus will not stack with other Specialties. Only one Specialty may apply at a time.
The Academics, Craft, Performance, and Science Skills all come with one free Specialty when you take your first rank in that Skill, representing the focus of your studies/practice.
There are few hard rules on what is allowed as a Specialty.
Not advisable to be as narrow as 'Underwater Basket Weaving'.
But not so broad that the associated Skill nearly always, or even mostly, gets the Specialty bonus.
For example: 'Muay Thai' as an Unarmed Skill Specialty would not be allowed because you could apply this Specialty to nearly every use of Unarmed.