It's very important to know your North and South nodes in your chart. They are great indications of what you have gone through and life lessons you may have experienced OR missed in your latest and recent past life experience (on the human time scale that is).
The North Node represents the original or main goal and focus for your current life as you (who you are) right now. Your life will more than likely put great emphasis on that aspect depending on the sign that is within your chart.
The South Node represents the past life experience you have had that kickstarted or created the karma you are experiencing today, and so you may need to learn how to let go from being that old unproductive way that you used to behave like.
For a quick example to put things into perspective, let's say that you are reincarnated in this life time as Lanetta Jenkins whose North Node is in Libra and South Node is in Aries. Lanetta J. in her past life may have been a government spy who is an assassin who snuck his way into a major country's government building to learn about the secrets of their new war plan to take over their neighboring country, and through his way of getting to the top of that social ladder, he may have harmed or killed a few people in the name of satisfying one's own goals for Self (thus, building up negative karma that may needs to be balanced out for that soul).
** Keep in mind this is hypothetical, and also keep in mind that Aries is the first sign of the zodiac and they are all about SELF, EGO, and need things taken care of and done NOW. Many astrologists like to use the analogy of the way a baby needs urgent care 24/7 in the way Aries does, but instead Aries will go ahead and get those things done on their own, without giving a damn who's in the way which makes them very FIERCE and FIESTY.
Now, continuing with that example, let's say that Lanetta Jenkins' North Node is in Libra, and in this lifetime (today) she is studying to be an immaculate and INCREDIBLE ballet dancer. And in the elite ballet dancing school that she attends, they're really big on learning how to ballet dance in coordination as a TEAM. Libra is an air sign that is all about FAIRNESS and EQUALITY and BALANCE. So the overall theme for her to learn in this lifetime is BALANCE between learning how to deal with other people (such as her dance partners and the way THEY dance).
Let's say that throughout ballet school, she graduates and heads to competitions with her friends as a TEAM, and they WIN as a TEAM. And ultimately, she becomes a legendary ballet teacher/judge and just so happens to end up on popular television shows such as 'Dancing With The Stars' where she can meticulously critique dancers and they way they move with their partners. As she does this, she inspires not only the celebrities, but also everyone who knows of her and her ELITE work, that partnership and BALANCE can be a very good and important thing.