The EOS 5D Mark III was the follow-up to the ground-breaking 5D Mark II. Released in 2012, the 5D III included the video features that made the 5D II so popular but added a 61 point autofocus system (very similar to the one found in the EOS-1D X) along with an upgraded metering sensor, a wider ISO range, dual memory card slots and 100% viewfinder coverage (just to name a few improvements).
B&H has its remaining Canon EOS 5D Mark III inventory nicely reduced. If you've been considering the upgrade to a full frame camera but your budget doesn't stretch to the 5D Mark IV, the 5D Mark III is still worthy of consideration.
For what it's worth, the Canon EOS SL1 / 100D was also discontinued.