Personality assessments are no longer just used by psychologists anymore - they have now made their way into the hands of companies across the country. A look at one of the most popular of these tests, the Myers-Briggs Type Indicator, gives insight into why so many organizations are beginning to trust its results in their hiring processes.

The Myers-Briggs Type Indicator is one of the most widely used personality inventories in the United States. It attempts to link people's personalities with one of 16 types based on four key traits. In the 1940s, Katharine Briggs and her daughter, Isabel Briggs Myers, invented the test, drawing on ideas from Carl Jung. Jung divided people into eight different types, but Myers and Briggs expanded on those, resulting in the 16profiles used on the test today.

Personality in four dimensions

There are several versions of the MBTI out there, including an extended one, but generally, it consists of approximately 25 questions aimed at determining a person's styles and preferences in four dimensions. Below is an in depth look at each of those dimensions.

Dimension One: Extroversion vs. Introversion

While many people immediately think of either a loud, talkative, party-loving person or a quiet, anti-social, bookish person when confronted with these terms, there is more to this dimension than these stereotypical images. Extroversion and introversion really refer to where an individual gets his or her energy.

"The primary difference between introverts and extroverts is how they recharge their batteries. extroverts are energized by the outer world ... introverts, on the other hand, are energized by the internal world - by ideas, impressions, and emotions," as Marti Olsen Laney expressed in her book "The Introvert Advantage."

Only when extroverts have been around people enough, can they have enough energy to be on their own. Similarly, introverts, once revved up, can actually be quite talkative in social settings.

Dimension Two: Sensing vs. Intuition

Perhaps two better words for this dimension would be observation and introspection. David Keirsey, author of the bestseller "Please Understand Me," has a website that explains this dimension in depth. "(Sensors) see what is in front of them and are usually accurate at catching details ... they want facts and trust facts ... they focus on what is happening, or what has happened, rather than (what might be)," Keirsey's website reports.

In contrast, intuitive people are more skilled at picking up on the realities of relationships of those around them. They excel at very quickly realizing the wider implications of a complex explanation or description they read, often skipping right over the verbal into "just knowing things."

While sensors can tell you exactly how they came to a conclusion, intuitives have a hard time retracing the decision gathering process.

Dimension Three: Thinking vs. Feeling

When making a tough decision, do you let your heart lead the way or do you use logic to make the final say? This dimension can tell you if you are ruled more by your emotions or by your reason.

As Otto Kroeger and Janet M. Thuesen put it in their book "Type Talk," "(Thinkers), in the decision-making process, prefer to be very logical, detached, analytical and driven by objective values as (they) come to conclusions. This group strives for justice and clarity."

Whereas when feelers make decisions, they are driven by their interpersonal involvement with the people concerned and are more subjective.

Dimension Four: Judging vs. Perceiving

The judgers of the world are the people who are always on time - or, are early - to the meeting. They are those who are always neat and clean, and they are endlessly planning in detail the events of the upcoming year, month, day and even the next ten minutes.

Without the judgers, the world would be very unorganized. But the perceivers offer their own special talents too. Perceivers are wonderfully adept at dealing with the unexpected. Because they often don't have a set plan, spontaneity is what makes their worlds exciting. They don't mind if the game goes into overtime or if their friend shows up half an hour late. judgers and perceivers also differ in the speed at which they make decisions.

Judgers tend to make quick judgments and stay with their initial conclusions, while perceivers have a hard time even making a concrete decision as they think it is better to keep their options open.

What's important to remember about the dimensions is that they are each a continuum; no one is completely introverted or completely extroverted. In fact, many people fall somewhere in the middle. And this is where, in some critic's opinions, the test fails.