Man is created to work.  He is always working toward a goal, but one might question the depth of his aimpoints. 

Most can imagine fulfillment, but for lack of a tangible objective, struggle to wean themselves from generally acknowledged superficiality.

Some tastes of fulfillment: a snuggling baby, sharing a meal, standing on a mountain peak, helping a friend, surfing the perfect wave or looking down the aisle at one's bride; all hint at perfection - how it ought to be.

Caught in controversy: man is drawn by what is seen yet pulled by what is known but unseen. 
Man is wired to achieve but struggles with determining what he should strive for.  Popular culture provides plenty to emulate but the people who are the epitome of this demonstrate they are not "happy". Despite what is seen, the populace idolizes celebrities, while celebrities envy their fans' anonymity.
DoggieHeadTilt Changing the culture requires first changing the conversation. If you keep using the same words and categories, you’re saying nothing has changed. You have to make the doggie head tilt if ears are going to perk up!
We are a called people on a journey: living, reading, studying, communicating.
Purpose
C.S. Lewis Institute
Ravi Zacharias
Artillerymen shoot at targets they can not see, often over mountains or even cities.  Accuracy is a function of geometry, combined with scientific estimates of non-standard conditions.  In this technologically advanced time, the most accurate method of determining direction is transferring "directional control" from the stars.  Yet using local "known points", a less accurate method, is usually deemed good enough.
Work
My mother-in-law says I "work on my computer.  I prefer to describe myself as thinking and dreaming via the laptop, it is the medium rather than the objective.  I also enjoy working on and driving an old Porsche, though I struggle to find real purpose in it - Joy is a key to this idea about how one works.

I also love "the deal".  I've  dabbled in cars and real estate and am learning the art and science of business.  Building a deal that gratifies all parties involved is part of the mandate for man to create.

Everyone works.  Even if it is for "play", one still has an objective.  Knowing you have a goal, what is your purpose?  Work that furthers relationships will be fulfilling in lasting ways.
Semper Fidelis
Presentation on Real Estate "Adventures"
The only Entreprenuerial endeavor I've made $ on is my hobby.
How does one determine his direction?  Some use Adam Smith's invisible hand theory to ascertain we are best off if everyone pursues his own self-interest, creating efficiency and growth.  Others might rely on guidance from parents, rules or laws to determine the best actions.  But even for the most prudent person the law does not always fit.  Everyone has a threshold upon which a "higher call" supercedes the rules?  Man can not devise an absolute right or wrong.
A good friend and mentor pointed out Adam Smith's thinking was a little deeper than looking out for oneself.  Smith said it is "the best head connected to the best heart" that makes for a prudent and judicious decision maker. 

To be accurate, one must look beyond the local known points to find guidance that transcends culture, government, and man.  Because of their distance, the stars are more accurate than local "map spots".  What is more accurate than the stars?
The most important research a midshipman, officer candidate or potential recruit undertakes is the attempt to match one's personality, abilities, and purpose to selecting a vocation.  Don't rely on movies or a casual observation to decide how you are going to work for the next 5-30 years.  Get as many impressions as you can by talking to service members young & old, both on and off of Active Duty.  A great book with objective observations on the military in general is Robert Kaplan's Hog Pilots Blue Water Grunts.
U. S. Marine Corps
I am honored and privileged to be a Marine.  I am part of something bigger than myself and doing  work in the service of others.  Most people search their entire lives for this; I was bestowed with it at age 23.   I am entrusted with responsibility, and assigned to work with outstanding people toward goals that are generally meaningful in lasting ways.  Marines are instilled with a sense of honor and resourcefulness.  The mentality that we develop from that leads to effectiveness that makes "Lean Thinking" seem indulgent.  Although I travel extensively and get to do cool things, by far the best part about being a Marine is serving with other Marines.


Click Here to go to the TBS MOS site
Click here to go to the USNA Marines Website
If you determine the Marine Corps is a good fit for you, then you will have the opportunity to tell the Corps what Military Occupation Specialty you desire.  Enlisted "poolees" will negotiate this as part of the contract with his/her recruiter.  For officers, exemplary performance at The Basic School is the best way to influence the assignment, though the decision is made first with the best interest of the Marine Corps in mind.  To get a little insight into each Officer MOS, download this PDF file that contains a 2-3 page primer on each specialty. MOS Handbook
This is another description of Marine Officer MOS's.  There is a lot of other good info at About.com.