The one thing I think every photographer can agree on is that light is the most important thing in your picture. You can have the most beautiful of landscapes or the most precious of children and it still be the worst picture ever if your lighting is not right. I'm not talking setting up white sheets and spending thousands of dollars on lighten equipment. I'm talking about this epidemic of making our photos too dark. 
For most this happens without us even knowing because a lot of us if not most of us pull out our point and shoot camera (which is totally cool) and we fire away unaware that our camera's sensor is telling the camera that it is lighter outside than it really it. Even the very best cameras can have this default problem. The best part is it's a simple thing to fix and almost every photo edited program even the most basic of "came with the camera" programs has a button that says lighten.
Here's why this matters.....

for the most part these two images are identical. Expect for the one on the bottom has simply been lightened with the "lighten" button. Now sure I could spend hours dodging and boosting this image to bring out more and more but this simple little lighten brought the flower out just a little bit more from the background drawing my attention to it......which is what I want it to too. Neither picture is bad it's just that by lighten the image I was able to bring out my subject and showcase its beauty a little bit more.

Consider the lightening of a photo a simple slight of hand type of trick. You aren't changes the photos purpose. You aren't deleting or coloring things that were or are not there. you are taking the photo and bringing it to life and the simplest of lightens can change so much. Take for instance......

I first glance there is nothing different about these photos but the longer you look the more the bottom seems to appear softer, more romantic, sweet almost. They're are both great shots (or at least I think so) the only difference is that I brought the light in and let it do what it was meant to do in the first place and was simply to shine.

Try playing around with giving your photos a slight lighten before saving them for printing. Play around you might be surprised with what you get.