I needed something that worked well for photographing people in indoor setting and low light situations. I also was very interested in achieving a clear, sharp image of my subject while blurring the background so that background stuff is not distracting and the focus remains on the subject. I've learned that these things in the photography world are referred to as depth of field and aperture. The aperture setting on your camera determines how much light is let in and it affects the depth of field. If you Google some of these terms you'll find stuff that explains it a lot better than I ever could.
After somewhat understanding all these things I realized that I needed a lens with a large aperture opening. These are represented by f-stops, hence the 1.4f in my lens description. Most lens that come with the camera only go down as far as 3.5f. The smaller the f-stop number the larger the aperture opening. I know that seems backwards and if you're really interested it's explained more here and here.
All of these were taken with no flash. It was already dark outside, so the only light was from our lamps. You can tell a big difference between these and the ones I posted yesterday that had natural light from the windows coming in.