ISTP

Introverted Sensing Thinking Perceiving (ISTP) is one of the sixteen personality types from personality type systems based on C.G. Jung, of which the best-known are the Myers-Briggs Type Indicator (MBTI), Keirsey Temperament Sorter, and Socionics.

Referring to Keirsey, ISTPs belong to the Artisan temperament and are called "Crafters".

In Socionics ISTps belong to the club of the pragmatists, the delta Quadra and are named "Craftsman". Another notation for ISTp is SLI (which is an acronym for Sensory-Logical Intratim, referring to the cognitive functions).

Myers-Briggs Characteristics
According to Myers-Briggs, ISTPs excel at analyzing situations to reach the heart of a problem so that they can swiftly implement a functional repair, making them ideally suited to the field of engineering. Naturally quiet people, they are interested in understanding how systems operate, focusing on efficient operation and structure. They are open to new information and approaches. But contrary to their seemingly detached natures, ISTPs are often capable of humorously insightful observations about the world around them, and can be closet "daredevils" who gravitate toward fast-moving and/or risky hobbies (such as bungee jumping, hang gliding, motorcycling, parachuting, SCUBA diving, etc.), recreational sports (such as downhill skiing, ice hockey, racing, etc.), and careers (such as aviation, firefighting, etc.).

Keirsey Characteristics
According to Keirsey, ISTPs, or "Crafter Artisans", are masters at using tools of every type--artistic, technological, martial. Although they are introverts, they are authoritarian in their interactions with others and influence people easily. They focus on accomplishing tasks efficiently.

Socionics Characteristics
According to Socionics, ISTps, or "pragmatists", are keen observers of the world around them, fascinated by the way different environments interact--two cultures juxtaposed or the differences between nature and civilization. ISTps like to be comfortable and prefer aesthetically pleasing surroundings. They are careful in their enterprises, prone to avoid high-risk business. With the tasks they undertake, they are methodical and detail-oriented, but also innovative in incorporating new ideas. ISTps have a tendency towards depression and pessimism that can paralyze them in the fact of problems. Since they are not expressive about their emotions, others may see them as detached and uninvolved. On the contrary, ISTps are highly sensitive to the ways that others behave towards or speak about them.

Resources

 * http://keirsey.com/personality/spit.html
 * http://www.myersbriggs.org/my-mbti-personality-type/
 * http://www.socionics.com/advan/prof/istp.htm