When it comes earning a living, do you work at a job or are you building a career?

Let's define our terms. A job is something you do where you invest your time and skills in exchange for money. You probably work within a defined schedule where you are expected, say, to put in 40 hours a week in exchange for an hourly rate or annual salary.

A career on the other hand is something that you build over time where, with every new assignment you take on, you go further on your journey.

Wherever you are on your entrepreneurial journey, you likely kicked off your career like many of us by taking a job, maybe at a large company, to gain some experience. But what do you have now: a job or a career?

One of the aspects that differentiates a job versus a career is when someone gets more excited about the time they spend outside the office. These are folks who have interesting hobbies - like running marathons, climbing mountains, or even collecting stamps - that they can't wait to get to after they finish up their daily work.  They are busy all weekend long having a blast - only to drag themselves to the office Monday morning.

There's nothing wrong with having a job, especially if it gives you the financial means and flexibility to better pursue your hobbies.

People who are invested in building a career, however, are much more focused on finding ways to learn and gain experience in their work as a way to go further toward fulfilling long-term goals, which might be running a company or starting one of their own.

People who are building careers are the ones who take the assignments that everyone else shies away from as a way to gain valuable experience and a new perspective, like the engineer who volunteers to work on a finance project to learn more about that side of the business. It all comes down to a desire to build a reputation and a work portfolio that will help you drive toward your ultimate goals.

I've find that when I talk to really successful people who have built impressive careers, they often look back with hindsight and realize that it was the time they pushed themselves outside their comfort zone that helped them the most when it came to making the most progress on their career journey. If fact, they lived outside their comfort zone. It's taking on the tasks and assignments that have a steep learning curve that tend to deliver the key insights and guideposts to helping them build their career of their dreams - even if they didn't always know what to expect when they took it on.

Career builders also tend to invest far more time in the office at the expense of outside activities. But, as one very successful career builder told me: "The first 40 hours are for the company. The rest are for me."

That speaks to a key difference: the company you work for owns your job; you own your career.

So ask yourself again what you have at the moment - and what you really want to have: a job or a career? There is no wrong answer, but knowing what you want can help you better frame the decisions you make in terms of where you really want to go in the future.