The second photo of this little series is a 737-700.

There are numerous changes to this aircraft when compared to the -300. The one visual difference is the aircraft's wing. The wing is longer overall, resulting in increased fuel capacity.

The engines are the -7 variant of the CFM56s. They provide more thrust and sound very different from the early model CFM56 turbofans.

Lastly, there's the two-crew "glass cockpit" with flat-panel displays and the interior which takes design cues from the 777.