We are each a combination of D and I and S and C.  Understanding those basic 4 types of behavior styles is the first, really great step in understanding your own personal wiring.

The next progression is to see how your mix of the 4 basic styles combine to make you uniquely YOU.

How those are mixed, high and low and in what proportions can be understood and used for greater effectiveness and better relationships.  But, for now, here is a way to begin to understand the basics of the four primary styles.

D- When a "D" walks into a room, they automatically think, "I can make this better!"  Better
 will differ from D to D, from day to day, from situation to situation.  But D's are change-
 oriented and they like a challenge.
I- When an "I" walks into that room, they automatically think, "I can make this more FUN!"  
Having fun, getting people to loosen up, connecting and networking makes an I's world go 
round.  They are change-oriented and they do like a party.
S- When the "D" walks into the room and wants to make it better and the "I" walks in and 
wants to make it more fun, the "S".....who was there before anyone else, made sure the 
room was the right temperature, has the coffee brewed, and has counted chairs to be sure 
everyone has a seat.....wants to go home.  More than anything S's do not like conflict. They
are comfortable with the status quo and they do not like change sounds like conflict. 
Changing to "better" and for "more fun" sounds like potential conflict and S's would prefer 
to miss that.
C- The "C" is probably not at this place where the D's and I's are changing things 
and the S's are leaving (or waiting patiently for the time for clean up).  Unless, there is 
a really good reason for them to be there.  When that reason or task is accomplished, they 
will go home. C's are task-oriented and are in pursuit of perfection, so have little time 
to waste.

No one is purely one of style but we do tend to have one, sometimes two, styles that are most natural.  Learning your style, embracing it, managing it, and using it to your (and for others’) advantage is smart and intentional. Live your life on purpose!