it all depends on the vehicle...
TRD: stands for Toyota Racing development.
The TRD package is deferent on every Toyota vehicle, on a Tocoma, i believe, it has better off-rode suspension, auto locking differentials, engine, transmission and diff skid plates, wheel flairs on some.
SR5 in todays market, is just another trim level, bucket seats (not leather), and a manual transmission in an option.
back in the day SR5 had a different meaning....the 'S' denoted Sport, 'R' denoted the RN motor code, and '5'
denoted the 5-speed transmission...so back in the day an SR5 was not available with an auto, but today it is! and today the engine code is not RN anymore.