Not to much I know about this plane either, but here's what little I do:

It was developed in the 1960's to replace the U-2. After the incident with Russia shooting down a U-2 over their terriotry the US government changed the requirements of the SR-71, it would have to take pictures outside of enemy airspace. Thanks to its ultra high tech cameras it has little trouble accomplishing this. The most famous aspect of the Blackbird is its speed, a whooping Mach 3. The friction is so high at this speed that after landing the Blackbirds skin has had a temperature of over 1800 degrees F. Heres a picture: